Thank for the review. Previous mail contains patch with an error. Here it is fixed.
Hello. Thanks for the fixes! See my 6 comments below.

And I have pushed more fixes on the branch. Please,
look and squash.

Now every sqlite struct Index is created with tnt struct
index_def inside. This allows us to use tnt index_def
in work with sqlite indexes in the same manner as with
tnt index and is a step to remove sqlite Index with
tnt index.
Fields coll_array, coll_id_array, aiColumn, sort_order
and zName are removed from Index. All usages of this
fields changed to usage of corresponding index_def
fields.
index_is_unique(), sql_index_collation() and
index_column_count() are removed with calls of
index_def corresponding fields.

Closes: #3369

---
Branch:
https://github.com/tarantool/tarantool/tree/sb/gh-3369-use-index-def-in-select-and-where
Issue:https://github.com/tarantool/tarantool/issues/3369

  src/box/sql.c                        |  54 ++-
  src/box/sql/analyze.c                |  85 ++---
  src/box/sql/build.c                  | 713 +++++++++++++++++------------------
  src/box/sql/delete.c                 |  10 +-
  src/box/sql/expr.c                   |  61 +--
  src/box/sql/fkey.c                   | 132 +++----
  src/box/sql/insert.c                 | 145 ++++---
  src/box/sql/pragma.c                 |  30 +-
  src/box/sql/select.c                 |   2 +-
  src/box/sql/sqliteInt.h              | 111 ++----
  src/box/sql/update.c                 |  39 +-
  src/box/sql/vdbeaux.c                |   2 +-
  src/box/sql/vdbemem.c                |  21 +-
  src/box/sql/where.c                  | 180 ++++-----
  src/box/sql/wherecode.c              | 102 ++---
  test/sql-tap/colname.test.lua        |   4 +-
  test/sql/message-func-indexes.result |   8 +-
  17 files changed, 821 insertions(+), 878 deletions(-)

diff --git a/src/box/sql.c b/src/box/sql.c
index 11353150e..24e37652e 100644
--- a/src/box/sql.c
+++ b/src/box/sql.c
@@ -1452,8 +1452,8 @@ int tarantoolSqlite3MakeTableFormat(Table *pTable, void *buf)

      /* If table's PK is single column which is INTEGER, then
       * treat it as strict type, not affinity.  */
-    if (pk_idx && pk_idx->nColumn == 1) {
-        int pk = pk_idx->aiColumn[0];
+    if (pk_idx != NULL && pk_idx->def->key_def->part_count == 1) {
+        int pk = pk_idx->def->key_def->parts[0].fieldno;

1. You again sent the patch with spaces instead of tabs. Please, cope
with it. Looks like you copied 'git diff/show' output. Either use format-patch
or use 'git --no-pager diff/show'.

          if (def->fields[pk].type == FIELD_TYPE_INTEGER)
              pk_forced_int = pk;
      }
diff --git a/src/box/sql/build.c b/src/box/sql/build.c
index 0da7d805b..662fc698e 100644
--- a/src/box/sql/build.c
+++ b/src/box/sql/build.c> @@ -2646,18 +2535,154 @@ addIndexToTable(Index * pIndex, Table * pTab)> +        struct Expr *column_expr = sqlite3ExprSkipCollate(expr);
+        if (column_expr->op != TK_COLUMN) {
+            sqlite3ErrorMsg(parse, tnt_errcode_desc(ER_UNSUPPORTED),
+                        "Tarantool", "functional indexes");

2. Patch to allow SQL_TARANTOOL_ERROR has been pushed today, so you can use
here diag_set again.

+            goto tnt_error;
+        }
+
@@ -2805,108 +2828,92 @@ sql_create_index(struct Parse *parse, struct Token *token,

3. Crash:

box.cfg{}
box.sql.execute('CREATE TABLE test (a int, b int, c int, PRIMARY KEY (a, a COLLATE kek, b, c))')
Process 15886 stopped
* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x80)
    frame #0: 0x000000010035f77b tarantool`sql_create_index(parse=0x000000010481f8b0, token=0x0000000000000000, tbl_name=0x0000000000000000, col_list=0x00000001029039d8, on_error=ON_CONFLICT_ACTION_DEFAULT, start=0x0000000000000000, where=0x0000000000000000, sort_order=SORT_ORDER_ASC, if_not_exist=false, idx_type='\x02') at build.c:2895
   2892         * PRIMARY KEY contains no repeated columns.
   2893         */
   2894        if (IsPrimaryKeyIndex(index)) {
-> 2895            struct key_part *parts = index->def->key_def->parts;
   2896            uint32_t part_count = index->def->key_def->part_count;
   2897            uint32_t new_part_count = 1;
   2898   
Target 0: (tarantool) stopped.

@@ -3070,54 +3080,17 @@ sql_create_index(struct Parse *parse, struct Token *token,
-/**
- * Return number of columns in given index.
- * If space is ephemeral, use internal
- * SQL structure to fetch the value.
- */
-uint32_t
-index_column_count(const Index *idx)
-{
-    assert(idx != NULL);
-    uint32_t space_id = SQLITE_PAGENO_TO_SPACEID(idx->tnum);
-    struct space *space = space_by_id(space_id);
-    /* It is impossible to find an ephemeral space by id. */
-    if (space == NULL)
-        return idx->nColumn;
-
-    uint32_t index_id = SQLITE_PAGENO_TO_INDEXID(idx->tnum);
-    struct index *index = space_index(space, index_id);
-    assert(index != NULL);
-    return index->def->key_def->part_count;
-}
-
-/** Return true if given index is unique and not nullable. */
-bool
-index_is_unique_not_null(const Index *idx)

4. Same as on the previous review. Still is used in a pair of places.
Are you sure? I searched through the whole project and didn't find it.
There is only a variable with the same name in one place.
-{
-    assert(idx != NULL);
-    uint32_t space_id = SQLITE_PAGENO_TO_SPACEID(idx->tnum);
-    struct space *space = space_by_id(space_id);
-    assert(space != NULL);
-
-    uint32_t index_id = SQLITE_PAGENO_TO_INDEXID(idx->tnum);
-    struct index *index = space_index(space, index_id);
-    assert(index != NULL);
-    return (index->def->opts.is_unique &&
-        !index->def->key_def->is_nullable);
+    sqlite3DbFree(db, name);
  }
diff --git a/src/box/sql/where.c b/src/box/sql/where.c
index c0c26ce29..225fddc23 100644
--- a/src/box/sql/where.c
+++ b/src/box/sql/where.c
@@ -2913,11 +2898,32 @@ whereLoopAddBtree(WhereLoopBuilder * pBuilder,    /* WHERE clause information */
           */
          Index *pFirst;    /* First of real indices on the table */
          memset(&sPk, 0, sizeof(Index));
-        sPk.nColumn = 1;
-        sPk.aiColumn = &aiColumnPk;
          sPk.aiRowLogEst = aiRowEstPk;
          sPk.onError = ON_CONFLICT_ACTION_REPLACE;
          sPk.pTable = pTab;
+
+        struct key_def *key_def = key_def_new(1);
+        if (key_def == NULL) {
+            pWInfo->pParse->nErr++;
+            pWInfo->pParse->rc = SQL_TARANTOOL_ERROR;
+            return SQL_TARANTOOL_ERROR;
+        }
+
+        key_def_set_part(key_def, 0, 0, pTab->def->fields[0].type,
+                 ON_CONFLICT_ACTION_ABORT,
+                 NULL, COLL_NONE, SORT_ORDER_ASC);
+
+        sPk.def = index_def_new(pTab->def->id, 0, "primary",
+                    sizeof("primary") - 1, TREE,
+                    &index_opts_default, key_def, NULL);

11. Where is sPk.def is deleted?
It is deleted in freeIndex() with sPk

5. I do not see any mention of freeIndex() in where.c. Where is it deleted?

sPk is declared on stack. If it was deleted with freeIndex, Tarantool
would crash.

+        key_def_delete(key_def);
+
+        if (sPk.def == NULL) {
+            pWInfo->pParse->nErr++;
+            pWInfo->pParse->rc = SQL_TARANTOOL_ERROR;
+            return SQL_TARANTOOL_ERROR;
+        }
+
          aiRowEstPk[0] = sql_space_tuple_log_count(pTab);
          aiRowEstPk[1] = 0;
          pFirst = pSrc->pTab->pIndex;

6. Where is the test, that I gave you on the previous review and that
lead to crash? Please, add it to the test suite. And the new test in
this review too.
---
Branch: https://github.com/tarantool/tarantool/tree/sb/gh-3369-use-index-def-in-select-and-where
Issue: https://github.com/tarantool/tarantool/issues/3369

 src/box/errcode.h                                  |   1 +
 src/box/sql.c                                      |  54 +-
 src/box/sql/analyze.c                              |  85 ++-
 src/box/sql/build.c                                | 727 ++++++++++-----------
 src/box/sql/delete.c                               |  10 +-
 src/box/sql/expr.c                                 |  61 +-
 src/box/sql/fkey.c                                 | 213 +++---
 src/box/sql/insert.c                               | 145 ++--
 src/box/sql/pragma.c                               |  30 +-
 src/box/sql/select.c                               |   2 +-
 src/box/sql/sqliteInt.h                            | 116 ++--
 src/box/sql/update.c                               |  39 +-
 src/box/sql/vdbeaux.c                              |   2 +-
 src/box/sql/vdbemem.c                              |  21 +-
 src/box/sql/where.c                                | 182 +++---
 src/box/sql/wherecode.c                            | 102 +--
 .../{collation.test.lua => collation1.test.lua}    |   0
 test/sql-tap/collation2.test.lua                   |  20 +
 test/sql-tap/colname.test.lua                      |   4 +-
 test/sql-tap/identifier_case.test.lua              |   4 +-
 test/sql/message-func-indexes.result               |   8 +-
 21 files changed, 899 insertions(+), 927 deletions(-)
 rename test/sql-tap/{collation.test.lua => collation1.test.lua} (100%)
 create mode 100755 test/sql-tap/collation2.test.lua

diff --git a/src/box/errcode.h b/src/box/errcode.h
index c76018cbf..2229c5cbd 100644
--- a/src/box/errcode.h
+++ b/src/box/errcode.h
@@ -215,6 +215,7 @@ struct errcode_record {
 	/*160 */_(ER_ACTION_MISMATCH,		"Field %d contains %s on conflict action, but %s in index parts") \
 	/*161 */_(ER_VIEW_MISSING_SQL,		"Space declared as a view must have SQL statement") \
 	/*162 */_(ER_FOREIGN_KEY_CONSTRAINT,	"Can not commit transaction: deferred foreign keys violations are not resolved") \
+	/*163 */_(ER_NO_SUCH_COLLATION,		"Collation '%s' does not exist") \
 
 /*
  * !IMPORTANT! Please follow instructions at start of the file
diff --git a/src/box/sql.c b/src/box/sql.c
index 03b4f156a..b00e8655d 100644
--- a/src/box/sql.c
+++ b/src/box/sql.c
@@ -1418,8 +1418,8 @@ int tarantoolSqlite3MakeTableFormat(Table *pTable, void *buf)
 
 	/* If table's PK is single column which is INTEGER, then
 	 * treat it as strict type, not affinity.  */
-	if (pk_idx && pk_idx->nColumn == 1) {
-		int pk = pk_idx->aiColumn[0];
+	if (pk_idx != NULL && pk_idx->def->key_def->part_count == 1) {
+		int pk = pk_idx->def->key_def->parts[0].fieldno;
 		if (def->fields[pk].type == FIELD_TYPE_INTEGER)
 			pk_forced_int = pk;
 	}
@@ -1530,20 +1530,19 @@ tarantoolSqlite3MakeTableOpts(Table *pTable, const char *zSql, char *buf)
  */
 int tarantoolSqlite3MakeIdxParts(SqliteIndex *pIndex, void *buf)
 {
-	struct space_def *def = pIndex->pTable->def;
-	assert(def != NULL);
+	struct field_def *fields = pIndex->pTable->def->fields;
+	struct key_def *key_def = pIndex->def->key_def;
 	const struct Enc *enc = get_enc(buf);
-	struct SqliteIndex *primary_index;
-	char *base = buf, *p;
-	int pk_forced_int = -1;
-
-	primary_index = sqlite3PrimaryKeyIndex(pIndex->pTable);
+	char *base = buf;
+	uint32_t pk_forced_int = UINT32_MAX;
+	struct SqliteIndex *primary_index =
+		sqlite3PrimaryKeyIndex(pIndex->pTable);
 
 	/* If table's PK is single column which is INTEGER, then
 	 * treat it as strict type, not affinity.  */
-	if (primary_index->nColumn == 1) {
-		int pk = primary_index->aiColumn[0];
-		if (def->fields[pk].type == FIELD_TYPE_INTEGER)
+	if (primary_index->def->key_def->part_count == 1) {
+		int pk = primary_index->def->key_def->parts[0].fieldno;
+		if (fields[pk].type == FIELD_TYPE_INTEGER)
 			pk_forced_int = pk;
 	}
 
@@ -1553,46 +1552,45 @@ int tarantoolSqlite3MakeIdxParts(SqliteIndex *pIndex, void *buf)
 	 * primary key columns. Query planner depends on this particular
 	 * data layout.
 	 */
-	int i, n = pIndex->nColumn;
-
-	p = enc->encode_array(base, n);
-	for (i = 0; i < n; i++) {
-		int col = pIndex->aiColumn[i];
-		assert(def->fields[col].is_nullable ==
-		       action_is_nullable(def->fields[col].nullable_action));
+	struct key_part *part = key_def->parts;
+	char *p = enc->encode_array(base, key_def->part_count);
+	for (uint32_t i = 0; i < key_def->part_count; ++i, ++part) {
+		uint32_t col = part->fieldno;
+		assert(fields[col].is_nullable ==
+		       action_is_nullable(fields[col].nullable_action));
 		const char *t;
 		if (pk_forced_int == col) {
 			t = "integer";
 		} else {
-			enum affinity_type affinity = def->fields[col].affinity;
-			t = convertSqliteAffinity(affinity,
-						  def->fields[col].is_nullable);
+			t = convertSqliteAffinity(fields[col].affinity,
+						  fields[col].is_nullable);
 		}
 		/* do not decode default collation */
-		uint32_t cid = pIndex->coll_id_array[i];
+		uint32_t cid = part->coll_id;
 		p = enc->encode_map(p, cid == COLL_NONE ? 5 : 6);
 		p = enc->encode_str(p, "type", sizeof("type")-1);
 		p = enc->encode_str(p, t, strlen(t));
 		p = enc->encode_str(p, "field", sizeof("field")-1);
 		p = enc->encode_uint(p, col);
 		if (cid != COLL_NONE) {
-			p = enc->encode_str(p, "collation", sizeof("collation")-1);
+			p = enc->encode_str(p, "collation",
+					    sizeof("collation") - 1);
 			p = enc->encode_uint(p, cid);
 		}
 		p = enc->encode_str(p, "is_nullable", 11);
-		p = enc->encode_bool(p, def->fields[col].is_nullable);
+		p = enc->encode_bool(p, fields[col].is_nullable);
 		p = enc->encode_str(p, "nullable_action", 15);
 		const char *action_str =
-			on_conflict_action_strs[def->fields[col].nullable_action];
+			on_conflict_action_strs[fields[col].nullable_action];
 		p = enc->encode_str(p, action_str, strlen(action_str));
 
 		p = enc->encode_str(p, "sort_order", 10);
-		enum sort_order sort_order = pIndex->sort_order[i];
+		enum sort_order sort_order = part->sort_order;
 		assert(sort_order < sort_order_MAX);
 		const char *sort_order_str = sort_order_strs[sort_order];
 		p = enc->encode_str(p, sort_order_str, strlen(sort_order_str));
 	}
-	return (int)(p - base);
+	return p - base;
 }
 
 /*
diff --git a/src/box/sql/analyze.c b/src/box/sql/analyze.c
index 5f73f026e..c5afff214 100644
--- a/src/box/sql/analyze.c
+++ b/src/box/sql/analyze.c
@@ -848,8 +848,7 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 	for (pIdx = pTab->pIndex; pIdx; pIdx = pIdx->pNext) {
 		int addrRewind;	/* Address of "OP_Rewind iIdxCur" */
 		int addrNextRow;	/* Address of "next_row:" */
-		const char *zIdxName;	/* Name of the index */
-		int nColTest;	/* Number of columns to test for changes */
+		const char *idx_name;	/* Name of the index */
 
 		if (pOnlyIdx && pOnlyIdx != pIdx)
 			continue;
@@ -857,17 +856,16 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 		 * names. Thus, for the sake of clarity, use
 		 * instead more familiar table name.
 		 */
-		if (IsPrimaryKeyIndex(pIdx)) {
-			zIdxName = pTab->def->name;
-		} else {
-			zIdxName = pIdx->zName;
-		}
-		nColTest = index_column_count(pIdx);
+		if (IsPrimaryKeyIndex(pIdx))
+			idx_name = pTab->def->name;
+		else
+			idx_name = pIdx->def->name;
+		int part_count = pIdx->def->key_def->part_count;
 
 		/* Populate the register containing the index name. */
-		sqlite3VdbeLoadString(v, regIdxname, zIdxName);
+		sqlite3VdbeLoadString(v, regIdxname, idx_name);
 		VdbeComment((v, "Analysis for %s.%s", pTab->def->name,
-			zIdxName));
+			    idx_name));
 
 		/*
 		 * Pseudo-code for loop that calls stat_push():
@@ -906,7 +904,7 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 		 * when building a record to insert into the sample column of
 		 * the _sql_stat4 table).
 		 */
-		pParse->nMem = MAX(pParse->nMem, regPrev + nColTest);
+		pParse->nMem = MAX(pParse->nMem, regPrev + part_count);
 
 		/* Open a read-only cursor on the index being analyzed. */
 		struct space *space =
@@ -917,7 +915,7 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 		sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pIdx->tnum,
 				  space_ptr_reg);
 		sql_vdbe_set_p4_key_def(pParse, pIdx);
-		VdbeComment((v, "%s", pIdx->zName));
+		VdbeComment((v, "%s", pIdx->def->name));
 
 		/* Invoke the stat_init() function. The arguments are:
 		 *
@@ -930,8 +928,8 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 		 * The third argument is only used for STAT4
 		 */
 		sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regStat4 + 3);
-		sqlite3VdbeAddOp2(v, OP_Integer, nColTest, regStat4 + 1);
-		sqlite3VdbeAddOp2(v, OP_Integer, nColTest, regStat4 + 2);
+		sqlite3VdbeAddOp2(v, OP_Integer, part_count, regStat4 + 1);
+		sqlite3VdbeAddOp2(v, OP_Integer, part_count, regStat4 + 2);
 		sqlite3VdbeAddOp4(v, OP_Function0, 0, regStat4 + 1, regStat4,
 				  (char *)&statInitFuncdef, P4_FUNCDEF);
 		sqlite3VdbeChangeP5(v, 3);
@@ -949,11 +947,11 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 		sqlite3VdbeAddOp2(v, OP_Integer, 0, regChng);
 		addrNextRow = sqlite3VdbeCurrentAddr(v);
 
-		if (nColTest > 0) {
+		if (part_count > 0) {
 			int endDistinctTest = sqlite3VdbeMakeLabel(v);
 			int *aGotoChng;	/* Array of jump instruction addresses */
 			aGotoChng =
-			    sqlite3DbMallocRawNN(db, sizeof(int) * nColTest);
+			    sqlite3DbMallocRawNN(db, sizeof(int) * part_count);
 			if (aGotoChng == 0)
 				continue;
 
@@ -969,7 +967,7 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 			 */
 			sqlite3VdbeAddOp0(v, OP_Goto);
 			addrNextRow = sqlite3VdbeCurrentAddr(v);
-			if (nColTest == 1 && index_is_unique(pIdx)) {
+			if (part_count == 1 && pIdx->def->opts.is_unique) {
 				/* For a single-column UNIQUE index, once we have found a non-NULL
 				 * row, we know that all the rest will be distinct, so skip
 				 * subsequent distinctness tests.
@@ -978,13 +976,12 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 						  endDistinctTest);
 				VdbeCoverage(v);
 			}
-			for (i = 0; i < nColTest; i++) {
-				uint32_t id;
-				struct coll *coll =
-					sql_index_collation(pIdx, i, &id);
+			struct key_part *part = pIdx->def->key_def->parts;
+			for (i = 0; i < part_count; ++i, ++part) {
+				struct coll *coll = part->coll;
 				sqlite3VdbeAddOp2(v, OP_Integer, i, regChng);
 				sqlite3VdbeAddOp3(v, OP_Column, iIdxCur,
-						  pIdx->aiColumn[i], regTemp);
+						  part->fieldno, regTemp);
 				aGotoChng[i] =
 				    sqlite3VdbeAddOp4(v, OP_Ne, regTemp, 0,
 						      regPrev + i, (char *)coll,
@@ -992,7 +989,7 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 				sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
 				VdbeCoverage(v);
 			}
-			sqlite3VdbeAddOp2(v, OP_Integer, nColTest, regChng);
+			sqlite3VdbeAddOp2(v, OP_Integer, part_count, regChng);
 			sqlite3VdbeGoto(v, endDistinctTest);
 
 			/*
@@ -1003,11 +1000,11 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 			 *  ...
 			 */
 			sqlite3VdbeJumpHere(v, addrNextRow - 1);
-			for (i = 0; i < nColTest; i++) {
+			part = pIdx->def->key_def->parts;
+			for (i = 0; i < part_count; ++i, ++part) {
 				sqlite3VdbeJumpHere(v, aGotoChng[i]);
 				sqlite3VdbeAddOp3(v, OP_Column, iIdxCur,
-						  pIdx->aiColumn[i],
-						  regPrev + i);
+						  part->fieldno, regPrev + i);
 			}
 			sqlite3VdbeResolveLabel(v, endDistinctTest);
 			sqlite3DbFree(db, aGotoChng);
@@ -1022,19 +1019,18 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 		 */
 		assert(regKey == (regStat4 + 2));
 		Index *pPk = sqlite3PrimaryKeyIndex(pIdx->pTable);
-		int j, k, regKeyStat;
-		int nPkColumn = (int)index_column_count(pPk);
-		regKeyStat = sqlite3GetTempRange(pParse, nPkColumn);
-		for (j = 0; j < nPkColumn; j++) {
-			k = pPk->aiColumn[j];
-			assert(k >= 0 && k < (int)pTab->def->field_count);
-			sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, k, regKeyStat + j);
-			VdbeComment((v, "%s",
-				pTab->def->fields[pPk->aiColumn[j]].name));
+		int pk_part_count = (int) pPk->def->key_def->part_count;
+		int regKeyStat = sqlite3GetTempRange(pParse, pk_part_count);
+		for (int j = 0; j < pk_part_count; ++j) {
+			int k = pPk->def->key_def->parts[j].fieldno;
+			assert(k >= 0 && k < (int) pTab->def->field_count);
+			sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, k,
+					  regKeyStat + j);
+			VdbeComment((v, "%s", pTab->def->fields[k].name));
 		}
 		sqlite3VdbeAddOp3(v, OP_MakeRecord, regKeyStat,
-				  nPkColumn, regKey);
-		sqlite3ReleaseTempRange(pParse, regKeyStat, nPkColumn);
+				  pk_part_count, regKey);
+		sqlite3ReleaseTempRange(pParse, regKeyStat, pk_part_count);
 
 		assert(regChng == (regStat4 + 1));
 		sqlite3VdbeAddOp4(v, OP_Function0, 1, regStat4, regTemp,
@@ -1057,11 +1053,11 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 		int regDLt = regStat1 + 2;
 		int regSample = regStat1 + 3;
 		int regCol = regStat1 + 4;
-		int regSampleKey = regCol + nColTest;
+		int regSampleKey = regCol + part_count;
 		int addrNext;
 		int addrIsNull;
 
-		pParse->nMem = MAX(pParse->nMem, regCol + nColTest);
+		pParse->nMem = MAX(pParse->nMem, regCol + part_count);
 
 		addrNext = sqlite3VdbeCurrentAddr(v);
 		callStatGet(v, regStat4, STAT_GET_KEY, regSampleKey);
@@ -1077,12 +1073,11 @@ analyzeOneTable(Parse * pParse,	/* Parser context */
 		 * be taken
 		 */
 		VdbeCoverageNeverTaken(v);
-		for (i = 0; i < nColTest; i++) {
-			sqlite3ExprCodeLoadIndexColumn(pParse, pIdx,
-									 iTabCur, i,
-									 regCol + i);
+		for (i = 0; i < part_count; i++) {
+			sqlite3ExprCodeLoadIndexColumn(pParse, pIdx, iTabCur, i,
+						       regCol + i);
 		}
-		sqlite3VdbeAddOp3(v, OP_MakeRecord, regCol, nColTest,
+		sqlite3VdbeAddOp3(v, OP_MakeRecord, regCol, part_count,
 				  regSample);
 		sqlite3VdbeAddOp3(v, OP_MakeRecord, regTabname, 6, regTemp);
 		sqlite3VdbeAddOp2(v, OP_IdxReplace, iStatCur + 1, regTemp);
@@ -1146,7 +1141,7 @@ analyzeTable(Parse * pParse, Table * pTab, Index * pOnlyIdx)
 	iStatCur = pParse->nTab;
 	pParse->nTab += 3;
 	if (pOnlyIdx) {
-		openStatTable(pParse, iStatCur, pOnlyIdx->zName, "idx");
+		openStatTable(pParse, iStatCur, pOnlyIdx->def->name, "idx");
 	} else {
 		openStatTable(pParse, iStatCur, pTab->def->name, "tbl");
 	}
diff --git a/src/box/sql/build.c b/src/box/sql/build.c
index 3737a119f..48e0b8d5e 100644
--- a/src/box/sql/build.c
+++ b/src/box/sql/build.c
@@ -241,6 +241,8 @@ static void
 freeIndex(sqlite3 * db, Index * p)
 {
 	sql_expr_delete(db, p->pPartIdxWhere, false);
+	if (p->def != NULL)
+		index_def_delete(p->def);
 	sqlite3DbFree(db, p->zColAff);
 	sqlite3DbFree(db, p);
 }
@@ -259,7 +261,8 @@ sqlite3UnlinkAndDeleteIndex(sqlite3 * db, Index * pIndex)
 
 	struct session *user_session = current_session();
 
-	pIndex = sqlite3HashInsert(&pIndex->pTable->idxHash, pIndex->zName, 0);
+	pIndex = sqlite3HashInsert(&pIndex->pTable->idxHash,
+				   pIndex->def->name, 0);
 	if (ALWAYS(pIndex)) {
 		if (pIndex->pTable->pIndex == pIndex) {
 			pIndex->pTable->pIndex = pIndex->pNext;
@@ -364,7 +367,7 @@ deleteTable(sqlite3 * db, Table * pTable)
 		pNext = pIndex->pNext;
 		assert(pIndex->pSchema == pTable->pSchema);
 		if ((db == 0 || db->pnBytesFreed == 0)) {
-			char *zName = pIndex->zName;
+			char *zName = pIndex->def->name;
 			TESTONLY(Index *
 				 pOld =) sqlite3HashInsert(&pTable->idxHash,
 							   zName, 0);
@@ -1026,7 +1029,7 @@ sqlite3AddCollateType(Parse * pParse, Token * pToken)
 	Table *p = pParse->pNewTable;
 	if (p == NULL)
 		return;
-	int i = p->def->field_count - 1;
+	uint32_t i = p->def->field_count - 1;
 	sqlite3 *db = pParse->db;
 	char *zColl = sqlite3NameFromToken(db, pToken);
 	if (!zColl)
@@ -1034,22 +1037,21 @@ sqlite3AddCollateType(Parse * pParse, Token * pToken)
 	uint32_t *id = &p->def->fields[i].coll_id;
 	p->aCol[i].coll = sql_get_coll_seq(pParse, zColl, id);
 	if (p->aCol[i].coll != NULL) {
-		Index *pIdx;
 		/* If the column is declared as "<name> PRIMARY KEY COLLATE <type>",
 		 * then an index may have been created on this column before the
 		 * collation type was added. Correct this if it is the case.
 		 */
-		for (pIdx = p->pIndex; pIdx; pIdx = pIdx->pNext) {
-			assert(pIdx->nColumn == 1);
-			if (pIdx->aiColumn[0] == i) {
-				id = &pIdx->coll_id_array[0];
-				pIdx->coll_array[0] =
+		for (struct Index *pIdx = p->pIndex; pIdx != NULL;
+		     pIdx = pIdx->pNext) {
+			assert(pIdx->def->key_def->part_count == 1);
+			if (pIdx->def->key_def->parts[0].fieldno == i) {
+				id = &pIdx->def->key_def->parts[0].coll_id;
+				pIdx->def->key_def->parts[0].coll =
 					sql_column_collation(p->def, i, id);
 			}
 		}
-	} else {
-		sqlite3DbFree(db, zColl);
 	}
+	sqlite3DbFree(db, zColl);
 }
 
 struct coll *
@@ -1079,66 +1081,6 @@ sql_column_collation(struct space_def *def, uint32_t column, uint32_t *coll_id)
 	return space->format->fields[column].coll;
 }
 
-struct key_def*
-sql_index_key_def(struct Index *idx)
-{
-	uint32_t space_id = SQLITE_PAGENO_TO_SPACEID(idx->tnum);
-	uint32_t index_id = SQLITE_PAGENO_TO_INDEXID(idx->tnum);
-	struct space *space = space_by_id(space_id);
-	assert(space != NULL);
-	struct index *index = space_index(space, index_id);
-	assert(index != NULL && index->def != NULL);
-	return index->def->key_def;
-}
-
-struct coll *
-sql_index_collation(Index *idx, uint32_t column, uint32_t *coll_id)
-{
-	assert(idx != NULL);
-	uint32_t space_id = SQLITE_PAGENO_TO_SPACEID(idx->pTable->tnum);
-	struct space *space = space_by_id(space_id);
-
-	assert(column < idx->nColumn);
-	/*
-	 * If space is still under construction, or it is
-	 * an ephemeral space, then fetch collation from
-	 * SQL internal structure.
-	 */
-	if (space == NULL) {
-		assert(column < idx->nColumn);
-		*coll_id = idx->coll_id_array[column];
-		return idx->coll_array[column];
-	}
-
-	struct key_def *key_def = sql_index_key_def(idx);
-	assert(key_def != NULL && key_def->part_count >= column);
-	*coll_id = key_def->parts[column].coll_id;
-	return key_def->parts[column].coll;
-}
-
-enum sort_order
-sql_index_column_sort_order(Index *idx, uint32_t column)
-{
-	assert(idx != NULL);
-	uint32_t space_id = SQLITE_PAGENO_TO_SPACEID(idx->pTable->tnum);
-	struct space *space = space_by_id(space_id);
-
-	assert(column < idx->nColumn);
-	/*
-	 * If space is still under construction, or it is
-	 * an ephemeral space, then fetch collation from
-	 * SQL internal structure.
-	 */
-	if (space == NULL) {
-		assert(column < idx->nColumn);
-		return idx->sort_order[column];
-	}
-
-	struct key_def *key_def = sql_index_key_def(idx);
-	assert(key_def != NULL && key_def->part_count >= column);
-	return key_def->parts[column].sort_order;
-}
-
 struct ExprList *
 space_checks_expr_list(uint32_t space_id)
 {
@@ -1322,17 +1264,6 @@ createTableStmt(sqlite3 * db, Table * p)
 	return zStmt;
 }
 
-/* Return true if value x is found any of the first nCol entries of aiCol[]
- */
-static int
-hasColumn(const i16 * aiCol, int nCol, int x)
-{
-	while (nCol-- > 0)
-		if (x == *(aiCol++))
-			return 1;
-	return 0;
-}
-
 /*
  * This routine runs at the end of parsing a CREATE TABLE statement.
  * The job of this routine is to convert both
@@ -1349,13 +1280,12 @@ static void
 convertToWithoutRowidTable(Parse * pParse, Table * pTab)
 {
 	Index *pPk;
-	int i, j;
 	sqlite3 *db = pParse->db;
 
 	/* Mark every PRIMARY KEY column as NOT NULL (except for imposter tables)
 	 */
 	if (!db->init.imposterTable) {
-		for (i = 0; i < (int)pTab->def->field_count; i++) {
+		for (uint32_t i = 0; i < pTab->def->field_count; i++) {
 			if (pTab->aCol[i].is_primkey) {
 				pTab->def->fields[i].nullable_action
 					= ON_CONFLICT_ACTION_ABORT;
@@ -1387,20 +1317,6 @@ convertToWithoutRowidTable(Parse * pParse, Table * pTab)
 		pTab->iPKey = -1;
 	} else {
 		pPk = sqlite3PrimaryKeyIndex(pTab);
-
-		/*
-		 * Remove all redundant columns from the PRIMARY KEY.  For example, change
-		 * "PRIMARY KEY(a,b,a,b,c,b,c,d)" into just "PRIMARY KEY(a,b,c,d)".  Later
-		 * code assumes the PRIMARY KEY contains no repeated columns.
-		 */
-		for (i = j = 1; i < pPk->nColumn; i++) {
-			if (hasColumn(pPk->aiColumn, j, pPk->aiColumn[i])) {
-				pPk->nColumn--;
-			} else {
-				pPk->aiColumn[j++] = pPk->aiColumn[i];
-			}
-		}
-		pPk->nColumn = j;
 	}
 	assert(pPk != 0);
 }
@@ -1482,7 +1398,7 @@ createIndex(Parse * pParse, Index * pIndex, int iSpaceId, int iIndexId,
 	}
 	sqlite3VdbeAddOp4(v,
 			  OP_String8, 0, iFirstCol + 2, 0,
-			  sqlite3DbStrDup(pParse->db, pIndex->zName),
+			  sqlite3DbStrDup(pParse->db, pIndex->def->name),
 			  P4_DYNAMIC);
 	sqlite3VdbeAddOp4(v, OP_String8, 0, iFirstCol + 3, 0, "tree",
 			  P4_STATIC);
@@ -1519,7 +1435,7 @@ makeIndexSchemaRecord(Parse * pParse,
 
 	sqlite3VdbeAddOp4(v,
 			  OP_String8, 0, iFirstCol, 0,
-			  sqlite3DbStrDup(pParse->db, pIndex->zName),
+			  sqlite3DbStrDup(pParse->db, pIndex->def->name),
 			  P4_DYNAMIC);
 
 	if (pParse->pNewTable) {
@@ -2448,15 +2364,16 @@ sqlite3RefillIndex(Parse * pParse, Index * pIndex, int memRootPage)
 	} else {
 		tnum = pIndex->tnum;
 	}
-	struct key_def *def = key_def_dup(sql_index_key_def(pIndex));
+	struct key_def *def = key_def_dup(pIndex->def->key_def);
 	if (def == NULL) {
 		sqlite3OomFault(db);
 		return;
 	}
 	/* Open the sorter cursor if we are to use one. */
 	iSorter = pParse->nTab++;
-	sqlite3VdbeAddOp4(v, OP_SorterOpen, iSorter, 0, pIndex->nColumn,
-			  (char *)def, P4_KEYDEF);
+	sqlite3VdbeAddOp4(v, OP_SorterOpen, iSorter, 0,
+			  pIndex->def->key_def->part_count, (char *)def,
+			  P4_KEYDEF);
 
 	/* Open the table. Loop through all rows of the table, inserting index
 	 * records into the sorter.
@@ -2487,7 +2404,8 @@ sqlite3RefillIndex(Parse * pParse, Index * pIndex, int memRootPage)
 		sqlite3VdbeGoto(v, j2);
 		addr2 = sqlite3VdbeCurrentAddr(v);
 		sqlite3VdbeAddOp4Int(v, OP_SorterCompare, iSorter, j2,
-				     regRecord, pIndex->nColumn);
+				     regRecord,
+				     pIndex->def->key_def->part_count);
 		VdbeCoverage(v);
 		parser_emit_unique_constraint(pParse, ON_CONFLICT_ACTION_ABORT,
 					      pIndex);
@@ -2507,44 +2425,15 @@ sqlite3RefillIndex(Parse * pParse, Index * pIndex, int memRootPage)
 	sqlite3VdbeAddOp1(v, OP_Close, iSorter);
 }
 
-/*
- * Allocate heap space to hold an Index object with nCol columns.
- *
- * Increase the allocation size to provide an extra nExtra bytes
- * of 8-byte aligned space after the Index object and return a
- * pointer to this extra space in *ppExtra.
- */
-Index *
-sqlite3AllocateIndexObject(sqlite3 * db,	/* Database connection */
-			   i16 nCol,	/* Total number of columns in the index */
-			   int nExtra,	/* Number of bytes of extra space to alloc */
-			   char **ppExtra	/* Pointer to the "extra" space */
-    )
+struct Index *
+sql_index_alloc(struct sqlite3 *db, uint32_t part_count)
 {
-	Index *p;		/* Allocated index object */
-	int nByte;		/* Bytes of space for Index object + arrays */
-
-	nByte = ROUND8(sizeof(Index)) +		    /* Index structure   */
-	    ROUND8(sizeof(struct coll *) * nCol) +  /* Index.coll_array  */
-	    ROUND8(sizeof(uint32_t) * nCol) +       /* Index.coll_id_array*/
-	    ROUND8(sizeof(LogEst) * (nCol + 1) +    /* Index.aiRowLogEst */
-		   sizeof(i16) * nCol +		    /* Index.aiColumn    */
-		   sizeof(enum sort_order) * nCol); /* Index.sort_order  */
-	p = sqlite3DbMallocZero(db, nByte + nExtra);
-	if (p) {
-		char *pExtra = ((char *)p) + ROUND8(sizeof(Index));
-		p->coll_array = (struct coll **)pExtra;
-		pExtra += ROUND8(sizeof(struct coll **) * nCol);
-		p->coll_id_array = (uint32_t *) pExtra;
-		pExtra += ROUND8(sizeof(uint32_t) * nCol);
-		p->aiRowLogEst = (LogEst *) pExtra;
-		pExtra += sizeof(LogEst) * (nCol + 1);
-		p->aiColumn = (i16 *) pExtra;
-		pExtra += sizeof(i16) * nCol;
-		p->sort_order = (enum sort_order *) pExtra;
-		p->nColumn = nCol;
-		*ppExtra = ((char *)p) + nByte;
-	}
+	/* Size of struct Index and aiRowLogEst. */
+	int nByte = ROUND8(sizeof(struct Index)) +
+		    ROUND8(sizeof(LogEst) * (part_count + 1));
+	struct Index *p = sqlite3DbMallocZero(db, nByte);
+	if (p != NULL)
+		p->aiRowLogEst = (LogEst *) ((char *)p + ROUND8(sizeof(*p)));
 	return p;
 }
 
@@ -2631,46 +2520,187 @@ addIndexToTable(Index * pIndex, Table * pTab)
 	}
 }
 
-bool
-index_is_unique(Index *idx)
-{
-	assert(idx != NULL);
-	uint32_t space_id = SQLITE_PAGENO_TO_SPACEID(idx->tnum);
-	uint32_t index_id = SQLITE_PAGENO_TO_INDEXID(idx->tnum);
-	struct space *space = space_by_id(space_id);
-	assert(space != NULL);
-	struct index *tnt_index = space_index(space, index_id);
-	assert(tnt_index != NULL);
+/**
+ * Allocate memory on parser region and copy given string (part of
+ * the sql statement) into the allocated memory.
+ * @param parse Parse context.
+ * @param str String (a part of sql statement) to be copied.
+ *
+ * @retval size Appended size.
+ */
+static int
+sql_append(struct Parse *parse, const char *str)
+{
+	const size_t str_len = strlen(str);
+	char *str_part = region_alloc(&parse->region, str_len);
+	if (str_part == NULL) {
+		diag_set(OutOfMemory, str_len, "region_alloc", "str_part");
+		parse->rc = SQL_TARANTOOL_ERROR;
+		parse->nErr++;
+		return 0;
+	}
+	memcpy(str_part, str, str_len);
+	return str_len;
+}
+
+/**
+ * Create and set index_def in the given Index.
+ *
+ * @param parse Parse context.
+ * @param index Index for which index_def should be created. It is
+ *              used only to set index_def at the end of the
+ *              function.
+ * @param table Table which is indexed by 'index' param.
+ * @param iid Index ID.
+ * @param name Index name.
+ * @param name_len Index name length.
+ * @param is_unique Is given 'index' unique or not.
+ * @param expr_list List of expressions, describe which columns
+ *                  of 'table' are used in index and also their
+ *                  collations, orders, etc.
+ * @param idx_type Index type, one of the following:
+ *                 SQLITE_IDXTYPE_APPDEF 0 (Index is created with
+ *                 CREATE INDEX statement)
+ *                 SQLITE_IDXTYPE_UNIQUE 1 (Index is created
+ *                 automatically to implement a UNIQUE constraint)
+ *                 SQLITE_IDXTYPE_PRIMARYKEY 2 (Index is a PRIMARY
+ *                 KEY).
+ */
+static void
+set_index_def(struct Parse *parse, struct Index *index, struct Table *table,
+	      uint32_t iid, const char *name, uint32_t name_len, bool is_unique,
+	      struct ExprList *expr_list, u8 idx_type)
+{
+	struct space_def *space_def = table->def;
+	size_t sql_size = 0;
+	struct index_opts opts;
+	index_opts_create(&opts);
+	index->def = NULL;
+	opts.is_unique = is_unique;
+
+	struct key_def *key_def = key_def_new(expr_list->nExpr);
+	if (key_def == NULL)
+		goto tnt_error;
+
+	/* Build initial parts of SQL statement.  */
+	if (idx_type == SQLITE_IDXTYPE_APPDEF) {
+		sql_size += sql_append(parse, "CREATE INDEX ");
+		sql_size += sql_append(parse, name);
+		sql_size += sql_append(parse, " ON ");
+		sql_size += sql_append(parse, space_def->name);
+		sql_size += sql_append(parse, " (");
+	}
+
+	for (int i = 0; i < expr_list->nExpr; i++) {
+		struct Expr *expr = expr_list->a[i].pExpr;
+		sql_resolve_self_reference(parse, table, NC_IdxExpr, expr, 0);
+		if (parse->nErr > 0)
+			goto cleanup;
+
+		struct Expr *column_expr = sqlite3ExprSkipCollate(expr);
+		if (column_expr->op != TK_COLUMN) {
+			diag_set(ClientError, ER_UNSUPPORTED, "Tarantool",
+				 "functional indexes");
+			goto tnt_error;
+		}
+
+		uint32_t fieldno = column_expr->iColumn;
+		const char *column_name = column_expr->u.zToken;
+		uint32_t coll_id;
+		struct coll *coll;
+		if (expr->op == TK_COLLATE) {
+			coll = sql_get_coll_seq(parse, expr->u.zToken,
+						&coll_id);
+			if (coll == NULL &&
+			    strcasecmp(expr->u.zToken, "binary") != 0) {
+				diag_set(ClientError, ER_NO_SUCH_COLLATION,
+					 expr->u.zToken);
+				goto tnt_error;
+			}
+			if (idx_type == SQLITE_IDXTYPE_APPDEF) {
+				sql_size += sql_append(parse, column_name);
+				sql_size += sql_append(parse, " COLLATE ");
+				sql_size += sql_append(parse, expr->u.zToken);
+				sql_size += sql_append(parse, ", ");
+			}
+		} else {
+			coll = sql_column_collation(space_def, fieldno,
+						    &coll_id);
+			if (idx_type == SQLITE_IDXTYPE_APPDEF) {
+				sql_size += sql_append(parse, column_name);
+				sql_size += sql_append(parse, ", ");
+			}
+		}
+		/*
+		 * Tarantool: DESC indexes are not supported so
+		 * far.
+		 */
+		key_def_set_part(key_def, i, fieldno,
+				 space_def->fields[fieldno].type,
+				 space_def->fields[fieldno].nullable_action,
+				 coll, coll_id, SORT_ORDER_ASC);
+	}
+	if (parse->nErr > 0)
+		goto cleanup;
 
-	return tnt_index->def->opts.is_unique;
+	if (idx_type == SQLITE_IDXTYPE_APPDEF) {
+		opts.sql = region_join(&parse->region, sql_size);
+		if (opts.sql == NULL) {
+			diag_set(OutOfMemory, sql_size, "region_join",
+				 "opts.sql");
+			goto tnt_error;
+		}
+		/*
+		 * fix last ", " with ")\0" to finish statement.
+		 */
+		memcpy(&opts.sql[sql_size - 2], ")\0", 2);
+	}
+
+	struct key_def *pk_key_def;
+	if (idx_type == SQLITE_IDXTYPE_APPDEF)
+		pk_key_def = table->pIndex->def->key_def;
+	else
+		pk_key_def = NULL;
+
+	index->def = index_def_new(space_def->id, iid, name, name_len, TREE,
+				   &opts, key_def, pk_key_def);
+	if (index->def == NULL)
+		goto tnt_error;
+cleanup:
+	if (key_def != NULL)
+		key_def_delete(key_def);
+	return;
+tnt_error:
+	parse->rc = SQL_TARANTOOL_ERROR;
+	++parse->nErr;
+	goto cleanup;
 }
 
 void
 sql_create_index(struct Parse *parse, struct Token *token,
 		 struct SrcList *tbl_name, struct ExprList *col_list,
-		 int on_error, struct Token *start, struct Expr *where,
-		 enum sort_order sort_order, bool if_not_exist, u8 idx_type)
-{
-	Table *pTab = 0;	/* Table to be indexed */
-	Index *pIndex = 0;	/* The index to be created */
-	char *zName = 0;	/* Name of the index */
-	int nName;		/* Number of characters in zName */
-	int i, j;
-	DbFixer sFix;		/* For assigning database names to pTable */
-	sqlite3 *db = parse->db;
-	struct ExprList_item *col_listItem;	/* For looping over col_list */
-	int nExtra = 0;		/* Space allocated for zExtra[] */
-	char *zExtra = 0;	/* Extra space after the Index object */
+		 enum on_conflict_action on_error, struct Token *start,
+		 struct Expr *where, enum sort_order sort_order,
+		 bool if_not_exist, u8 idx_type)
+{
+	/* Table to be indexed.  */
+	struct Table *table = NULL;
+	/* The index to be created.  */
+	struct Index *index = NULL;
+	/* Name of the index.  */
+	char *name = NULL;
+	int name_len;
+	struct sqlite3 *db = parse->db;
 	struct session *user_session = current_session();
 
-	if (db->mallocFailed || parse->nErr > 0) {
+	if (db->mallocFailed || parse->nErr > 0)
 		goto exit_create_index;
-	}
-	/* Do not account nested operations: the count of such
-	 * operations depends on Tarantool data dictionary internals,
-	 * such as data layout in system spaces. Also do not account
-	 * PRIMARY KEY and UNIQUE constraint - they had been accounted
-	 * in CREATE TABLE already.
+	/*
+	 * Do not account nested operations: the count of such
+	 * operations depends on Tarantool data dictionary
+	 * internals, such as data layout in system spaces. Also
+	 * do not account PRIMARY KEY and UNIQUE constraint - they
+	 * had been accounted in CREATE TABLE already.
 	 */
 	if (!parse->nested && idx_type == SQLITE_IDXTYPE_APPDEF) {
 		Vdbe *v = sqlite3GetVdbe(parse);
@@ -2681,39 +2711,43 @@ sql_create_index(struct Parse *parse, struct Token *token,
 	assert(db->pSchema != NULL);
 
 	/*
-	 * Find the table that is to be indexed.  Return early if not found.
+	 * Find the table that is to be indexed.
+	 * Return early if not found.
 	 */
 	if (tbl_name != NULL) {
-
-		/* Use the two-part index name to determine the database
-		 * to search for the table. 'Fix' the table name to this db
-		 * before looking up the table.
+		/*
+		 * Use the two-part index name to determine the
+		 * database to search for the table. 'Fix' the
+		 * table name to this db before looking up the
+		 * table.
 		 */
 		assert(token && token->z);
-
-		sqlite3FixInit(&sFix, parse, "index", token);
-		if (sqlite3FixSrcList(&sFix, tbl_name)) {
-			/* Because the parser constructs tbl_name from a single identifier,
+		DbFixer db_fixer;
+		sqlite3FixInit(&db_fixer, parse, "index", token);
+		if (sqlite3FixSrcList(&db_fixer, tbl_name)) {
+			/*
+			 * Because the parser constructs tbl_name
+			 * from a single identifier,
 			 * sqlite3FixSrcList can never fail.
 			 */
-			assert(0);
+			unreachable();
 		}
-		pTab = sqlite3LocateTable(parse, 0, tbl_name->a[0].zName);
-		assert(db->mallocFailed == 0 || pTab == 0);
-		if (pTab == 0)
+		table = sqlite3LocateTable(parse, 0, tbl_name->a[0].zName);
+		assert(db->mallocFailed == 0 || table == NULL);
+		if (table == NULL)
 			goto exit_create_index;
-		sqlite3PrimaryKeyIndex(pTab);
+		sqlite3PrimaryKeyIndex(table);
 	} else {
 		assert(token == NULL);
 		assert(start == NULL);
-		pTab = parse->pNewTable;
-		if (!pTab)
+		table = parse->pNewTable;
+		if (table == NULL)
 			goto exit_create_index;
 	}
 
-	assert(pTab != 0);
+	assert(table != NULL);
 	assert(parse->nErr == 0);
-	if (pTab->def->opts.is_view) {
+	if (table->def->opts.is_view) {
 		sqlite3ErrorMsg(parse, "views may not be indexed");
 		goto exit_create_index;
 	}
@@ -2731,42 +2765,38 @@ sql_create_index(struct Parse *parse, struct Token *token,
 	 * primary key or UNIQUE constraint.  We have to invent
 	 * our own name.
 	 */
-	if (token) {
-		zName = sqlite3NameFromToken(db, token);
-		if (zName == 0)
+	if (token != NULL) {
+		name = sqlite3NameFromToken(db, token);
+		if (name == NULL)
 			goto exit_create_index;
-		assert(token->z != 0);
+		assert(token->z != NULL);
 		if (!db->init.busy) {
-			if (sqlite3HashFind(&db->pSchema->tblHash, zName) !=
+			if (sqlite3HashFind(&db->pSchema->tblHash, name) !=
 			    NULL) {
-				sqlite3ErrorMsg(parse,
-						"there is already a table named %s",
-						zName);
+				sqlite3ErrorMsg(parse, "there is already a "\
+						"table named %s", name);
 				goto exit_create_index;
 			}
 		}
-		if (sqlite3HashFind(&pTab->idxHash, zName) != NULL) {
+		if (sqlite3HashFind(&table->idxHash, name) != NULL) {
 			if (!if_not_exist) {
 				sqlite3ErrorMsg(parse,
 						"index %s.%s already exists",
-						pTab->def->name, zName);
+						table->def->name, name);
 			} else {
 				assert(!db->init.busy);
 			}
 			goto exit_create_index;
 		}
 	} else {
-		int n;
-		Index *pLoop;
-		for (pLoop = pTab->pIndex, n = 1; pLoop;
+		int n = 1;
+		for (struct Index *pLoop = table->pIndex; pLoop != NULL;
 		     pLoop = pLoop->pNext, n++) {
 		}
-		zName =
-		    sqlite3MPrintf(db, "sqlite_autoindex_%s_%d", pTab->def->name,
-				   n);
-		if (zName == 0) {
+		name = sqlite3MPrintf(db, "sqlite_autoindex_%s_%d",
+				      table->def->name, n);
+		if (name == NULL)
 			goto exit_create_index;
-		}
 	}
 
 	/*
@@ -2776,9 +2806,9 @@ sql_create_index(struct Parse *parse, struct Token *token,
 	 * simulate this.
 	 */
 	if (col_list == NULL) {
-		Token prevCol;
-		uint32_t last_field = pTab->def->field_count - 1;
-		sqlite3TokenInit(&prevCol, pTab->def->fields[last_field].name);
+		struct Token prevCol;
+		uint32_t last_field = table->def->field_count - 1;
+		sqlite3TokenInit(&prevCol, table->def->fields[last_field].name);
 		col_list = sql_expr_list_append(parse->db, NULL,
 						sqlite3ExprAlloc(db, TK_ID,
 								 &prevCol, 0));
@@ -2790,108 +2820,93 @@ sql_create_index(struct Parse *parse, struct Token *token,
 		sqlite3ExprListCheckLength(parse, col_list, "index");
 	}
 
-	/* Figure out how many bytes of space are required to store explicitly
-	 * specified collation sequence names.
-	 */
-	for (i = 0; i < col_list->nExpr; i++) {
-		Expr *pExpr = col_list->a[i].pExpr;
-		assert(pExpr != 0);
-		if (pExpr->op == TK_COLLATE) {
-			nExtra += (1 + sqlite3Strlen30(pExpr->u.zToken));
-		}
-	}
+	/* Allocate the index structure.  */
+	name_len = sqlite3Strlen30(name);
 
-	/*
-	 * Allocate the index structure.
-	 */
-	nName = sqlite3Strlen30(zName);
-	pIndex = sqlite3AllocateIndexObject(db, col_list->nExpr,
-					    nName + nExtra + 1, &zExtra);
-	if (db->mallocFailed) {
+	if (name_len > BOX_NAME_MAX) {
+		sqlite3ErrorMsg(parse, "%s.%s exceeds indexes' names length "\
+				"limit", table->def->name, name);
 		goto exit_create_index;
 	}
-	assert(EIGHT_BYTE_ALIGNMENT(pIndex->aiRowLogEst));
-	assert(EIGHT_BYTE_ALIGNMENT(pIndex->coll_array));
-	pIndex->zName = zExtra;
-	zExtra += nName + 1;
-	memcpy(pIndex->zName, zName, nName + 1);
-	pIndex->pTable = pTab;
-	pIndex->onError = (u8) on_error;
+
+	if (sqlite3CheckIdentifierName(parse, name) != SQLITE_OK)
+		goto exit_create_index;
+
+	index = sql_index_alloc(db, col_list->nExpr);
+	if (db->mallocFailed)
+		goto exit_create_index;
+
+	assert(EIGHT_BYTE_ALIGNMENT(index->aiRowLogEst));
+	index->pTable = table;
+	index->onError = (u8) on_error;
 	/*
 	 * Don't make difference between UNIQUE indexes made by user
 	 * using CREATE INDEX statement and those created during
 	 * CREATE TABLE processing.
 	 */
 	if (idx_type == SQLITE_IDXTYPE_APPDEF &&
-	    on_error != ON_CONFLICT_ACTION_NONE) {
-		pIndex->idxType = SQLITE_IDXTYPE_UNIQUE;
-	} else {
-		pIndex->idxType = idx_type;
-	}
-	pIndex->pSchema = db->pSchema;
-	pIndex->nColumn = col_list->nExpr;
+	    on_error != ON_CONFLICT_ACTION_NONE)
+		index->idxType = SQLITE_IDXTYPE_UNIQUE;
+	else
+		index->idxType = idx_type;
+	index->pSchema = db->pSchema;
 	/* Tarantool have access to each column by any index */
-	if (where) {
-		sql_resolve_self_reference(parse, pTab, NC_PartIdx, where,
+	if (where != NULL) {
+		sql_resolve_self_reference(parse, table, NC_PartIdx, where,
 					   NULL);
-		pIndex->pPartIdxWhere = where;
+		index->pPartIdxWhere = where;
 		where = NULL;
 	}
 
-	/* Analyze the list of expressions that form the terms of the index and
-	 * report any errors.  In the common case where the expression is exactly
-	 * a table column, store that column in aiColumn[].
-	 *
-	 * TODO: Issue a warning if two or more columns of the index are identical.
-	 * TODO: Issue a warning if the table primary key is used as part of the
-	 * index key.
+	/*
+	 * TODO: Issue a warning if two or more columns of the
+	 * index are identical.
+	 * TODO: Issue a warning if the table primary key is used
+	 * as part of the index key.
 	 */
-	for (i = 0, col_listItem = col_list->a; i < col_list->nExpr;
-	     i++, col_listItem++) {
-		Expr *pCExpr;	/* The i-th index expression */
-		sql_resolve_self_reference(parse, pTab, NC_IdxExpr,
-					   col_listItem->pExpr, NULL);
-		if (parse->nErr > 0)
-			goto exit_create_index;
-		pCExpr = sqlite3ExprSkipCollate(col_listItem->pExpr);
-		if (pCExpr->op != TK_COLUMN) {
-			sqlite3ErrorMsg(parse,
-					"functional indexes aren't supported "
-					"in the current version");
-			goto exit_create_index;
-		} else {
-			j = pCExpr->iColumn;
-			assert(j <= 0x7fff);
-			if (j < 0) {
-				j = pTab->iPKey;
-			}
-			pIndex->aiColumn[i] = (i16) j;
-		}
-		struct coll *coll;
-		uint32_t id;
-		if (col_listItem->pExpr->op == TK_COLLATE) {
-			const char *coll_name = col_listItem->pExpr->u.zToken;
-			coll = sql_get_coll_seq(parse, coll_name, &id);
 
-			if (coll == NULL &&
-			    sqlite3StrICmp(coll_name, "binary") != 0) {
-				goto exit_create_index;
+	uint32_t max_iid = 0;
+	for (struct Index *index = table->pIndex; index != NULL;
+	     index = index->pNext) {
+		max_iid = max_iid > index->def->iid ?
+			  max_iid : index->def->iid + 1;
+	}
+
+	bool is_unique = on_error != ON_CONFLICT_ACTION_NONE;
+	set_index_def(parse,  index, table, max_iid, name, name_len,
+		      is_unique, col_list, idx_type);
+
+	if (index->def == NULL)
+		goto exit_create_index;
+	/*
+	 * Remove all redundant columns from the PRIMARY KEY.
+	 * For example, change "PRIMARY KEY(a,b,a,b,c,b,c,d)" into
+	 * just "PRIMARY KEY(a,b,c,d)". Later code assumes the
+	 * PRIMARY KEY contains no repeated columns.
+	 */
+	if (IsPrimaryKeyIndex(index)) {
+		struct key_part *parts = index->def->key_def->parts;
+		uint32_t part_count = index->def->key_def->part_count;
+		uint32_t new_part_count = 1;
+
+		for(uint32_t i = 1; i < part_count; i++) {
+			uint32_t j;
+			for(j = 0; j < new_part_count; j++) {
+				if(parts[i].fieldno == parts[j].fieldno)
+					break;
 			}
-		} else if (j >= 0) {
-			coll = sql_column_collation(pTab->def, j, &id);
-		} else {
-			id = COLL_NONE;
-			coll = NULL;
+
+			if (j == new_part_count)
+				parts[new_part_count++] = parts[i];
 		}
-		pIndex->coll_array[i] = coll;
-		pIndex->coll_id_array[i] = id;
 
-		/* Tarantool: DESC indexes are not supported so far.
-		 * See gh-3016.
-		 */
-		pIndex->sort_order[i] = SORT_ORDER_ASC;
+		index->def->key_def->part_count = new_part_count;
 	}
-	if (pTab == parse->pNewTable) {
+
+	if (!index_def_is_valid(index->def, table->def->name))
+		goto exit_create_index;
+
+	if (table == parse->pNewTable) {
 		/* This routine has been called to create an automatic index as a
 		 * result of a PRIMARY KEY or UNIQUE clause on a column definition, or
 		 * a PRIMARY KEY or UNIQUE clause following the column definitions.
@@ -2913,28 +2928,28 @@ sql_create_index(struct Parse *parse, struct Token *token,
 		 * the constraint occur in different orders, then the constraints are
 		 * considered distinct and both result in separate indices.
 		 */
-		Index *pIdx;
-		for (pIdx = pTab->pIndex; pIdx; pIdx = pIdx->pNext) {
-			int k;
+		for (struct Index *pIdx = table->pIndex; pIdx != NULL;
+		     pIdx = pIdx->pNext) {
+			uint32_t k;
 			assert(IsUniqueIndex(pIdx));
 			assert(pIdx->idxType != SQLITE_IDXTYPE_APPDEF);
-			assert(IsUniqueIndex(pIndex));
+			assert(IsUniqueIndex(index));
 
-			if (pIdx->nColumn != pIndex->nColumn)
+			if (pIdx->def->key_def->part_count !=
+			    index->def->key_def->part_count)
 				continue;
-			for (k = 0; k < pIdx->nColumn; k++) {
-				assert(pIdx->aiColumn[k] >= 0);
-				if (pIdx->aiColumn[k] != pIndex->aiColumn[k])
+			for (k = 0; k < pIdx->def->key_def->part_count; k++) {
+				if (pIdx->def->key_def->parts[k].fieldno !=
+				    index->def->key_def->parts[k].fieldno)
 					break;
 				struct coll *coll1, *coll2;
-				uint32_t id;
-				coll1 = sql_index_collation(pIdx, k, &id);
-				coll2 = sql_index_collation(pIndex, k, &id);
+				coll1 = pIdx->def->key_def->parts[k].coll;
+				coll2 = index->def->key_def->parts[k].coll;
 				if (coll1 != coll2)
 					break;
 			}
-			if (k == pIdx->nColumn) {
-				if (pIdx->onError != pIndex->onError) {
+			if (k == pIdx->def->key_def->part_count) {
+				if (pIdx->onError != index->onError) {
 					/* This constraint creates the same index as a previous
 					 * constraint specified somewhere in the CREATE TABLE statement.
 					 * However the ON CONFLICT clauses are different. If both this
@@ -2942,17 +2957,19 @@ sql_create_index(struct Parse *parse, struct Token *token,
 					 * ON CONFLICT clauses this is an error. Otherwise, use the
 					 * explicitly specified behavior for the index.
 					 */
-					if (!
-					    (pIdx->onError == ON_CONFLICT_ACTION_DEFAULT
-					     || pIndex->onError ==
-					     ON_CONFLICT_ACTION_DEFAULT)) {
+					if (pIdx->onError !=
+					    ON_CONFLICT_ACTION_DEFAULT &&
+					    index->onError !=
+					    ON_CONFLICT_ACTION_DEFAULT) {
 						sqlite3ErrorMsg(parse,
-								"conflicting ON CONFLICT clauses specified",
-								0);
-					}
-					if (pIdx->onError == ON_CONFLICT_ACTION_DEFAULT) {
-						pIdx->onError = pIndex->onError;
+								"conflicting "\
+								"ON CONFLICT "\
+								"clauses "\
+								"specified");
 					}
+					if (pIdx->onError ==
+					    ON_CONFLICT_ACTION_DEFAULT)
+						pIdx->onError = index->onError;
 				}
 				if (idx_type == SQLITE_IDXTYPE_PRIMARYKEY)
 					pIdx->idxType = idx_type;
@@ -2966,15 +2983,16 @@ sql_create_index(struct Parse *parse, struct Token *token,
 	 */
 	assert(parse->nErr == 0);
 	if (db->init.busy) {
-		Index *p;
-		p = sqlite3HashInsert(&pTab->idxHash, pIndex->zName, pIndex);
-		if (p) {
-			assert(p == pIndex);	/* Malloc must have failed */
+		struct Index *p = sqlite3HashInsert(&table->idxHash,
+						    index->def->name, index);
+		if (p != NULL) {
+			/* Malloc must have failed. */
+			assert(p == index);
 			sqlite3OomFault(db);
 			goto exit_create_index;
 		}
 		user_session->sql_flags |= SQLITE_InternChanges;
-		pIndex->tnum = db->init.newTnum;
+		index->tnum = db->init.newTnum;
 	}
 
 	/*
@@ -3025,14 +3043,14 @@ sql_create_index(struct Parse *parse, struct Token *token,
 				       ON_CONFLICT_ACTION_NONE ? "" : " UNIQUE",
 				       n, token->z);
 
-		iSpaceId = SQLITE_PAGENO_TO_SPACEID(pTab->tnum);
+		iSpaceId = SQLITE_PAGENO_TO_SPACEID(table->tnum);
 		iIndexId = getNewIid(parse, iSpaceId, iCursor);
 		sqlite3VdbeAddOp1(v, OP_Close, iCursor);
-		createIndex(parse, pIndex, iSpaceId, iIndexId, zStmt);
+		createIndex(parse, index, iSpaceId, iIndexId, zStmt);
 
 		/* consumes zStmt */
 		iFirstSchemaCol =
-		    makeIndexSchemaRecord(parse, pIndex, iSpaceId, iIndexId,
+		    makeIndexSchemaRecord(parse, index, iSpaceId, iIndexId,
 					  zStmt);
 
 		/* Reparse the schema. Code an OP_Expire
@@ -3055,54 +3073,17 @@ sql_create_index(struct Parse *parse, struct Token *token,
 
 	if (!db->init.busy && tbl_name != NULL)
 		goto exit_create_index;
-	addIndexToTable(pIndex, pTab);
-	pIndex = NULL;
+	addIndexToTable(index, table);
+	index = NULL;
 
 	/* Clean up before exiting */
  exit_create_index:
-	if (pIndex)
-		freeIndex(db, pIndex);
+	if (index != NULL)
+		freeIndex(db, index);
 	sql_expr_delete(db, where, false);
 	sql_expr_list_delete(db, col_list);
 	sqlite3SrcListDelete(db, tbl_name);
-	sqlite3DbFree(db, zName);
-}
-
-/**
- * Return number of columns in given index.
- * If space is ephemeral, use internal
- * SQL structure to fetch the value.
- */
-uint32_t
-index_column_count(const Index *idx)
-{
-	assert(idx != NULL);
-	uint32_t space_id = SQLITE_PAGENO_TO_SPACEID(idx->tnum);
-	struct space *space = space_by_id(space_id);
-	/* It is impossible to find an ephemeral space by id. */
-	if (space == NULL)
-		return idx->nColumn;
-
-	uint32_t index_id = SQLITE_PAGENO_TO_INDEXID(idx->tnum);
-	struct index *index = space_index(space, index_id);
-	assert(index != NULL);
-	return index->def->key_def->part_count;
-}
-
-/** Return true if given index is unique and not nullable. */
-bool
-index_is_unique_not_null(const Index *idx)
-{
-	assert(idx != NULL);
-	uint32_t space_id = SQLITE_PAGENO_TO_SPACEID(idx->tnum);
-	struct space *space = space_by_id(space_id);
-	assert(space != NULL);
-
-	uint32_t index_id = SQLITE_PAGENO_TO_INDEXID(idx->tnum);
-	struct index *index = space_index(space, index_id);
-	assert(index != NULL);
-	return (index->def->opts.is_unique &&
-		!index->def->key_def->is_nullable);
+	sqlite3DbFree(db, name);
 }
 
 void
@@ -3728,9 +3709,9 @@ parser_emit_unique_constraint(struct Parse *parser,
 	const struct space_def *def = index->pTable->def;
 	StrAccum err_accum;
 	sqlite3StrAccumInit(&err_accum, parser->db, 0, 0, 200);
-	for (int j = 0; j < index->nColumn; ++j) {
-		assert(index->aiColumn[j] >= 0);
-		const char *col_name = def->fields[index->aiColumn[j]].name;
+	struct key_part *part = index->def->key_def->parts;
+	for (uint32_t j = 0; j < index->def->key_def->part_count; ++j, ++part) {
+		const char *col_name = def->fields[part->fieldno].name;
 		if (j != 0)
 			sqlite3StrAccumAppend(&err_accum, ", ", 2);
 		sqlite3XPrintf(&err_accum, "%s.%s", def->name, col_name);
@@ -3751,11 +3732,11 @@ static bool
 collationMatch(struct coll *coll, struct Index *index)
 {
 	assert(coll != NULL);
-	for (int i = 0; i < index->nColumn; i++) {
-		uint32_t id;
-		struct coll *idx_coll = sql_index_collation(index, i, &id);
-		assert(idx_coll != 0 || index->aiColumn[i] < 0);
-		if (index->aiColumn[i] >= 0 && coll == idx_coll)
+	struct key_part *part = index->def->key_def->parts;
+	for (uint32_t i = 0; i < index->def->key_def->part_count; i++, part++) {
+		struct coll *idx_coll = part->coll;
+		assert(idx_coll != NULL);
+		if (coll == idx_coll)
 			return true;
 	}
 	return false;
diff --git a/src/box/sql/delete.c b/src/box/sql/delete.c
index 5a799714d..5a7cf7652 100644
--- a/src/box/sql/delete.c
+++ b/src/box/sql/delete.c
@@ -268,11 +268,12 @@ sql_table_delete_from(struct Parse *parse, struct SrcList *tab_list,
 
 		/* Extract the primary key for the current row */
 		if (!is_view) {
-			for (int i = 0; i < pk_len; i++) {
+			struct key_part *part = pk_def->parts;
+			for (int i = 0; i < pk_len; i++, part++) {
 				struct space_def *def = space->def;
 				sqlite3ExprCodeGetColumnOfTable(v, def,
 								tab_cursor,
-								pk_def->parts[i].fieldno,
+								part->fieldno,
 								reg_pk + i);
 			}
 		} else {
@@ -568,13 +569,14 @@ sql_generate_index_key(struct Parse *parse, struct Index *index, int cursor,
 			*part_idx_label = 0;
 		}
 	}
-	int col_cnt = index_column_count(index);
+	int col_cnt = index->def->key_def->part_count;
 	int reg_base = sqlite3GetTempRange(parse, col_cnt);
 	if (prev != NULL && (reg_base != reg_prev ||
 			     prev->pPartIdxWhere != NULL))
 		prev = NULL;
 	for (int j = 0; j < col_cnt; j++) {
-		if (prev != NULL && prev->aiColumn[j] == index->aiColumn[j]) {
+		if (prev != NULL && prev->def->key_def->parts[j].fieldno ==
+				    index->def->key_def->parts[j].fieldno) {
 			/*
 			 * This column was already computed by the
 			 * previous index.
diff --git a/src/box/sql/expr.c b/src/box/sql/expr.c
index 70e134f21..00d8dedd8 100644
--- a/src/box/sql/expr.c
+++ b/src/box/sql/expr.c
@@ -2405,21 +2405,28 @@ sqlite3FindInIndex(Parse * pParse,	/* Parsing context */
 			     pIdx = pIdx->pNext) {
 				Bitmask colUsed; /* Columns of the index used */
 				Bitmask mCol;	/* Mask for the current column */
-				if (pIdx->nColumn < nExpr)
+				uint32_t part_count =
+					pIdx->def->key_def->part_count;
+				struct key_part *parts =
+					pIdx->def->key_def->parts;
+				if ((int)part_count < nExpr)
 					continue;
 				/* Maximum nColumn is BMS-2, not BMS-1, so that we can compute
 				 * BITMASK(nExpr) without overflowing
 				 */
-				testcase(pIdx->nColumn == BMS - 2);
-				testcase(pIdx->nColumn == BMS - 1);
-				if (pIdx->nColumn >= BMS - 1)
+				testcase(part_count == BMS - 2);
+				testcase(part_count == BMS - 1);
+				if (part_count >= BMS - 1)
+					continue;
+				if (mustBeUnique &&
+				    ((int)part_count > nExpr ||
+				     !pIdx->def->opts.is_unique)) {
+					/*
+					 * This index is not
+					 * unique over the IN RHS
+					 * columns.
+					 */
 					continue;
-				if (mustBeUnique) {
-					if (pIdx->nColumn > nExpr
-					    || (pIdx->nColumn > nExpr
-					    && !index_is_unique(pIdx))) {
-							continue;	/* This index is not unique over the IN RHS columns */
-					}
 				}
 
 				colUsed = 0;	/* Columns of index used so far */
@@ -2432,16 +2439,15 @@ sqlite3FindInIndex(Parse * pParse,	/* Parsing context */
 					int j;
 
 					for (j = 0; j < nExpr; j++) {
-						if (pIdx->aiColumn[j] !=
-						    pRhs->iColumn) {
+						if ((int) parts[j].fieldno !=
+						    pRhs->iColumn)
 							continue;
-						}
-						struct coll *idx_coll;
-						idx_coll = sql_index_collation(pIdx, j, &id);
+
+						struct coll *idx_coll =
+							     parts[j].coll;
 						if (pReq != NULL &&
-						    pReq != idx_coll) {
+						    pReq != idx_coll)
 							continue;
-						}
 						break;
 					}
 					if (j == nExpr)
@@ -2466,18 +2472,17 @@ sqlite3FindInIndex(Parse * pParse,	/* Parsing context */
 							  0, 0, 0,
 							  sqlite3MPrintf(db,
 							  "USING INDEX %s FOR IN-OPERATOR",
-							  pIdx->zName),
+							  pIdx->def->name),
 							  P4_DYNAMIC);
 					struct space *space =
 						space_by_id(SQLITE_PAGENO_TO_SPACEID(pIdx->tnum));
 					vdbe_emit_open_cursor(pParse, iTab,
 							      pIdx->tnum, space);
-					VdbeComment((v, "%s", pIdx->zName));
+					VdbeComment((v, "%s", pIdx->def->name));
 					assert(IN_INDEX_INDEX_DESC ==
 					       IN_INDEX_INDEX_ASC + 1);
 					eType = IN_INDEX_INDEX_ASC +
-						sql_index_column_sort_order(pIdx,
-									    0);
+						parts[0].sort_order;
 
 					if (prRhsHasNull) {
 #ifdef SQLITE_ENABLE_COLUMN_USED_MASK
@@ -2499,7 +2504,7 @@ sqlite3FindInIndex(Parse * pParse,	/* Parsing context */
 							/* Tarantool: Check for null is performed on first key of the index.  */
 							sqlite3SetHasNullFlag(v,
 									      iTab,
-									      pIdx->aiColumn[0],
+									      parts[0].fieldno,
 									      *prRhsHasNull);
 						}
 					}
@@ -3130,12 +3135,12 @@ sqlite3ExprCodeIN(Parse * pParse,	/* Parsing and code generating context */
 		struct Index *pk = sqlite3PrimaryKeyIndex(tab);
 		assert(pk);
 
+		uint32_t fieldno = pk->def->key_def->parts[0].fieldno;
 		enum affinity_type affinity =
-			tab->def->fields[pk->aiColumn[0]].affinity;
-		if (pk->nColumn == 1
-		    && affinity == AFFINITY_INTEGER
-		    && pk->aiColumn[0] < nVector) {
-			int reg_pk = rLhs + pk->aiColumn[0];
+			tab->def->fields[fieldno].affinity;
+		if (pk->def->key_def->part_count == 1 &&
+		    affinity == AFFINITY_INTEGER && (int)fieldno < nVector) {
+			int reg_pk = rLhs + (int)fieldno;
 			sqlite3VdbeAddOp2(v, OP_MustBeInt, reg_pk, destIfFalse);
 		}
 	}
@@ -3467,7 +3472,7 @@ sqlite3ExprCodeLoadIndexColumn(Parse * pParse,	/* The parsing context */
 			       int regOut	/* Store the index column value in this register */
     )
 {
-	i16 iTabCol = pIdx->aiColumn[iIdxCol];
+	i16 iTabCol = pIdx->def->key_def->parts[iIdxCol].fieldno;
 	sqlite3ExprCodeGetColumnOfTable(pParse->pVdbe, pIdx->pTable->def,
 					iTabCur, iTabCol, regOut);
 }
diff --git a/src/box/sql/fkey.c b/src/box/sql/fkey.c
index 6c75c4772..2b96bde7e 100644
--- a/src/box/sql/fkey.c
+++ b/src/box/sql/fkey.c
@@ -213,7 +213,6 @@ sqlite3FkLocateIndex(Parse * pParse,	/* Parse context to store any error in */
 		     int **paiCol	/* OUT: Map of index columns in pFKey */
     )
 {
-	Index *pIdx = 0;	/* Value to return via *ppIdx */
 	int *aiCol = 0;		/* Value to return via *paiCol */
 	int nCol = pFKey->nCol;	/* Number of columns in parent key */
 	char *zKey = pFKey->aCol[0].zCol;	/* Name of left-most parent key column */
@@ -255,83 +254,86 @@ sqlite3FkLocateIndex(Parse * pParse,	/* Parse context to store any error in */
 		*paiCol = aiCol;
 	}
 
-	for (pIdx = pParent->pIndex; pIdx; pIdx = pIdx->pNext) {
-		int nIdxCol = index_column_count(pIdx);
-		if (nIdxCol == nCol && index_is_unique(pIdx)
-		    && pIdx->pPartIdxWhere == 0) {
-			/* pIdx is a UNIQUE index (or a PRIMARY KEY) and has the right number
-			 * of columns. If each indexed column corresponds to a foreign key
-			 * column of pFKey, then this index is a winner.
+	struct Index *index = NULL;
+	for (index = pParent->pIndex; index != NULL; index = index->pNext) {
+		int part_count = index->def->key_def->part_count;
+		if (part_count != nCol || !index->def->opts.is_unique ||
+		    index->pPartIdxWhere != NULL)
+			continue;
+		/*
+		 * Index is a UNIQUE index (or a PRIMARY KEY) and
+		 * has the right number of columns. If each
+		 * indexed column corresponds to a foreign key
+		 * column of pFKey, then this index is a winner.
+		 */
+		if (zKey == NULL) {
+			/*
+			 * If zKey is NULL, then this foreign key
+			 * is implicitly mapped to the PRIMARY KEY
+			 * of table pParent. The PRIMARY KEY index
+			 * may be identified by the test.
 			 */
-
-			if (zKey == 0) {
-				/* If zKey is NULL, then this foreign key is implicitly mapped to
-				 * the PRIMARY KEY of table pParent. The PRIMARY KEY index may be
-				 * identified by the test.
-				 */
-				if (IsPrimaryKeyIndex(pIdx)) {
-					if (aiCol) {
-						int i;
-						for (i = 0; i < nCol; i++)
-							aiCol[i] =
-							    pFKey->aCol[i].
-							    iFrom;
-					}
-					break;
+			if (IsPrimaryKeyIndex(index)) {
+				if (aiCol != NULL) {
+					for (int i = 0; i < nCol; i++)
+						aiCol[i] = pFKey->aCol[i].iFrom;
 				}
-			} else {
-				/* If zKey is non-NULL, then this foreign key was declared to
-				 * map to an explicit list of columns in table pParent. Check if this
-				 * index matches those columns. Also, check that the index uses
-				 * the default collation sequences for each column.
+				break;
+			}
+		} else {
+			/*
+			 * If zKey is non-NULL, then this foreign
+			 * key was declared to map to an explicit
+			 * list of columns in table pParent. Check
+			 * if this index matches those columns.
+			 * Also, check that the index uses the
+			 * default collation sequences for each
+			 * column.
+			 */
+			int i, j;
+			struct key_part *part = index->def->key_def->parts;
+			for (i = 0; i < nCol; i++, part++) {
+				/*
+				 * Index of column in parent
+				 * table.
 				 */
-				int i, j;
-				for (i = 0; i < nCol; i++) {
-					i16 iCol = pIdx->aiColumn[i];	/* Index of column in parent tbl */
-					char *zIdxCol;	/* Name of indexed column */
-
-					if (iCol < 0)
-						break;	/* No foreign keys against expression indexes */
-
-					/* If the index uses a collation sequence that is different from
-					 * the default collation sequence for the column, this index is
-					 * unusable. Bail out early in this case.
-					 */
-					struct coll *def_coll;
-					uint32_t id;
-					def_coll = sql_column_collation(pParent->def,
-									iCol,
-									&id);
-					struct coll *coll =
-						sql_index_collation(pIdx, i,
-								    &id);
-					if (def_coll != coll)
-						break;
-
-					zIdxCol =
-						pParent->def->fields[iCol].name;
-					for (j = 0; j < nCol; j++) {
-						if (strcmp
-						    (pFKey->aCol[j].zCol,
-						     zIdxCol) == 0) {
-							if (aiCol)
-								aiCol[i] =
-								    pFKey->
-								    aCol[j].
-								    iFrom;
-							break;
-						}
-					}
-					if (j == nCol)
-						break;
+				i16 iCol = (int) part->fieldno;
+				/*
+				 * If the index uses a collation
+				 * sequence that is different from
+				 * the default collation sequence
+				 * for the column, this index is
+				 * unusable. Bail out early in
+				 * this case.
+				 */
+				uint32_t id;
+				struct coll *def_coll =
+					sql_column_collation(pParent->def,
+							     iCol, &id);
+				struct coll *coll = part->coll;
+				if (def_coll != coll)
+					break;
+
+				char *zIdxCol = pParent->def->fields[iCol].name;
+				for (j = 0; j < nCol; j++) {
+					if (strcmp(pFKey->aCol[j].zCol,
+						   zIdxCol) != 0)
+						continue;
+					if (aiCol)
+						aiCol[i] = pFKey->aCol[j].iFrom;
+					break;
 				}
-				if (i == nCol)
-					break;	/* pIdx is usable */
+				if (j == nCol)
+					break;
+			}
+			if (i == nCol) {
+				/* Index is usable. */
+				break;
 			}
 		}
 	}
 
-	if (!pIdx) {
+	if (index == NULL) {
 		if (!pParse->disableTriggers) {
 			sqlite3ErrorMsg(pParse,
 					"foreign key mismatch - \"%w\" referencing \"%w\"",
@@ -341,7 +343,7 @@ sqlite3FkLocateIndex(Parse * pParse,	/* Parse context to store any error in */
 		return 1;
 	}
 
-	*ppIdx = pIdx;
+	*ppIdx = index;
 	return 0;
 }
 
@@ -460,17 +462,19 @@ fkLookupParent(Parse * pParse,	/* Parse context */
 			 */
 			if (pTab == pFKey->pFrom && nIncr == 1) {
 				int iJump =
-				    sqlite3VdbeCurrentAddr(v) + nCol + 1;
-				for (i = 0; i < nCol; i++) {
+					sqlite3VdbeCurrentAddr(v) + nCol + 1;
+				struct key_part *part =
+					pIdx->def->key_def->parts;
+				for (i = 0; i < nCol; ++i, ++part) {
 					int iChild = aiCol[i] + 1 + regData;
-					int iParent =
-					    pIdx->aiColumn[i] + 1 + regData;
-					assert(pIdx->aiColumn[i] >= 0);
+					int iParent = 1 + regData +
+						      (int)part->fieldno;
 					assert(aiCol[i] != pTab->iPKey);
-					if (pIdx->aiColumn[i] == pTab->iPKey) {
+					if ((int)part->fieldno == pTab->iPKey) {
 						/* The parent key is a composite key that includes the IPK column */
 						iParent = regData;
 					}
+
 					sqlite3VdbeAddOp3(v, OP_Ne, iChild,
 							  iJump, iParent);
 					VdbeCoverage(v);
@@ -614,7 +618,6 @@ fkScanChildren(Parse * pParse,	/* Parse context */
     )
 {
 	sqlite3 *db = pParse->db;	/* Database handle */
-	int i;			/* Iterator variable */
 	Expr *pWhere = 0;	/* WHERE clause to scan with */
 	NameContext sNameContext;	/* Context used to resolve WHERE clause */
 	WhereInfo *pWInfo;	/* Context used by sqlite3WhereXXX() */
@@ -622,7 +625,7 @@ fkScanChildren(Parse * pParse,	/* Parse context */
 	Vdbe *v = sqlite3GetVdbe(pParse);
 
 	assert(pIdx == 0 || pIdx->pTable == pTab);
-	assert(pIdx == 0 || (int)index_column_count(pIdx) == pFKey->nCol);
+	assert(pIdx == 0 || (int) pIdx->def->key_def->part_count == pFKey->nCol);
 	assert(pIdx != 0);
 
 	if (nIncr < 0) {
@@ -639,19 +642,20 @@ fkScanChildren(Parse * pParse,	/* Parse context */
 	 * the parent key columns. The affinity of the parent key column should
 	 * be applied to each child key value before the comparison takes place.
 	 */
-	for (i = 0; i < pFKey->nCol; i++) {
+	for (int i = 0; i < pFKey->nCol; i++) {
 		Expr *pLeft;	/* Value from parent table row */
 		Expr *pRight;	/* Column ref to child table */
 		Expr *pEq;	/* Expression (pLeft = pRight) */
 		i16 iCol;	/* Index of column in child table */
-		const char *zCol;	/* Name of column in child table */
+		const char *column_name;
 
-		iCol = pIdx ? pIdx->aiColumn[i] : -1;
+		iCol = pIdx != NULL ?
+		       (int) pIdx->def->key_def->parts[i].fieldno : -1;
 		pLeft = exprTableRegister(pParse, pTab, regData, iCol);
 		iCol = aiCol ? aiCol[i] : pFKey->aCol[0].iFrom;
 		assert(iCol >= 0);
-		zCol = pFKey->pFrom->def->fields[iCol].name;
-		pRight = sqlite3Expr(db, TK_ID, zCol);
+		column_name = pFKey->pFrom->def->fields[iCol].name;
+		pRight = sqlite3Expr(db, TK_ID, column_name);
 		pEq = sqlite3PExpr(pParse, TK_EQ, pLeft, pRight);
 		pWhere = sqlite3ExprAnd(db, pWhere, pEq);
 	}
@@ -670,15 +674,14 @@ fkScanChildren(Parse * pParse,	/* Parse context */
 
 		Expr *pEq, *pAll = 0;
 		Index *pPk = sqlite3PrimaryKeyIndex(pTab);
-		assert(pIdx != 0);
-		int col_count = index_column_count(pPk);
-		for (i = 0; i < col_count; i++) {
-			i16 iCol = pIdx->aiColumn[i];
-			assert(iCol >= 0);
-			pLeft = exprTableRegister(pParse, pTab, regData, iCol);
-			pRight =
-				exprTableColumn(db, pTab->def,
-						pSrc->a[0].iCursor, iCol);
+		assert(pIdx != NULL);
+		uint32_t part_count = pPk->def->key_def->part_count;
+		for (uint32_t i = 0; i < part_count; i++) {
+			uint32_t fieldno = pIdx->def->key_def->parts[i].fieldno;
+			pLeft = exprTableRegister(pParse, pTab, regData,
+						  fieldno);
+			pRight = exprTableColumn(db, pTab->def,
+						 pSrc->a[0].iCursor, fieldno);
 			pEq = sqlite3PExpr(pParse, TK_EQ, pLeft, pRight);
 			pAll = sqlite3ExprAnd(db, pAll, pEq);
 		}
@@ -983,7 +986,6 @@ sqlite3FkCheck(Parse * pParse,	/* Parse context */
 			if (aiCol[i] == pTab->iPKey) {
 				aiCol[i] = -1;
 			}
-			assert(pIdx == 0 || pIdx->aiColumn[i] >= 0);
 		}
 
 		pParse->nTab++;
@@ -1108,19 +1110,19 @@ sqlite3FkOldmask(Parse * pParse,	/* Parse context */
 
 	if (user_session->sql_flags & SQLITE_ForeignKeys) {
 		FKey *p;
-		int i;
 		for (p = pTab->pFKey; p; p = p->pNextFrom) {
-			for (i = 0; i < p->nCol; i++)
+			for (int i = 0; i < p->nCol; i++)
 				mask |= COLUMN_MASK(p->aCol[i].iFrom);
 		}
 		for (p = sqlite3FkReferences(pTab); p; p = p->pNextTo) {
 			Index *pIdx = 0;
 			sqlite3FkLocateIndex(pParse, pTab, p, &pIdx, 0);
-			if (pIdx) {
-				int nIdxCol = index_column_count(pIdx);
-				for (i = 0; i < nIdxCol; i++) {
-					assert(pIdx->aiColumn[i] >= 0);
-					mask |= COLUMN_MASK(pIdx->aiColumn[i]);
+			if (pIdx != NULL) {
+				uint32_t part_count =
+					pIdx->def->key_def->part_count;
+				for (uint32_t i = 0; i < part_count; i++) {
+					mask |= COLUMN_MASK(pIdx->def->
+						key_def->parts[i].fieldno);
 				}
 			}
 		}
@@ -1264,11 +1266,12 @@ fkActionTrigger(struct Parse *pParse, struct Table *pTab, struct FKey *pFKey,
 			       || (pTab->iPKey >= 0
 				   && pTab->iPKey <
 				      (int)pTab->def->field_count));
-			assert(pIdx == 0 || pIdx->aiColumn[i] >= 0);
+
+			uint32_t fieldno = pIdx != NULL ?
+					   pIdx->def->key_def->parts[i].fieldno :
+					   (uint32_t)pTab->iPKey;
 			sqlite3TokenInit(&tToCol,
-					 pTab->def->fields[pIdx ? pIdx->
-						    aiColumn[i] : pTab->iPKey].
-					 name);
+					 pTab->def->fields[fieldno].name);
 			sqlite3TokenInit(&tFromCol,
 					 pFKey->pFrom->def->fields[
 						iFromCol].name);
diff --git a/src/box/sql/insert.c b/src/box/sql/insert.c
index c12043bde..762caaee5 100644
--- a/src/box/sql/insert.c
+++ b/src/box/sql/insert.c
@@ -89,14 +89,14 @@ sqlite3IndexAffinityStr(sqlite3 *db, Index *index)
 	 * sqliteDeleteIndex() when the Index structure itself is
 	 * cleaned up.
 	 */
-	int column_count = index_column_count(index);
+	int column_count = index->def->key_def->part_count;
 	index->zColAff = (char *) sqlite3DbMallocRaw(0, column_count + 1);
 	if (index->zColAff == NULL) {
 		sqlite3OomFault(db);
 		return NULL;
 	}
 	for (int n = 0; n < column_count; n++) {
-		uint16_t x = index->aiColumn[n];
+		uint16_t x = index->def->key_def->parts[n].fieldno;
 		index->zColAff[n] = index->pTable->def->fields[x].affinity;
 	}
 	index->zColAff[column_count] = 0;
@@ -647,7 +647,7 @@ sqlite3Insert(Parse * pParse,	/* Parser context */
 		     pIdx = pIdx->pNext, i++) {
 			assert(pIdx);
 			aRegIdx[i] = ++pParse->nMem;
-			pParse->nMem += index_column_count(pIdx);
+			pParse->nMem += pIdx->def->key_def->part_count;
 		}
 	}
 
@@ -1069,12 +1069,8 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 	Index *pIdx;		/* Pointer to one of the indices */
 	Index *pPk = 0;		/* The PRIMARY KEY index */
 	sqlite3 *db;		/* Database connection */
-	int i;			/* loop counter */
-	int ix;			/* Index loop counter */
-	int nCol;		/* Number of columns */
 	int addr1;		/* Address of jump instruction */
 	int seenReplace = 0;	/* True if REPLACE is used to resolve INT PK conflict */
-	int nPkField;		/* Number of fields in PRIMARY KEY. */
 	u8 isUpdate;		/* True if this is an UPDATE operation */
 	u8 bAffinityDone = 0;	/* True if the OP_Affinity operation has been run */
 	struct session *user_session = current_session();
@@ -1086,10 +1082,8 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 	struct space_def *def = pTab->def;
 	/* This table is not a VIEW */
 	assert(!def->opts.is_view);
-	nCol = def->field_count;
 
 	pPk = sqlite3PrimaryKeyIndex(pTab);
-	nPkField = index_column_count(pPk);
 
 	/* Record that this module has started */
 	VdbeModuleComment((v, "BEGIN: GenCnstCks(%d,%d,%d,%d,%d)",
@@ -1099,17 +1093,16 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 	enum on_conflict_action on_error;
 	/* Test all NOT NULL constraints.
 	 */
-	for (i = 0; i < nCol; i++) {
-		if (i == pTab->iPKey) {
+	for (uint32_t i = 0; i < def->field_count; i++) {
+		if ((int) i == pTab->iPKey)
 			continue;
-		}
 		if (aiChng && aiChng[i] < 0) {
 			/* Don't bother checking for NOT NULL on columns that do not change */
 			continue;
 		}
 		if (def->fields[i].is_nullable ||
 		    (pTab->tabFlags & TF_Autoincrement &&
-		     pTab->iAutoIncPKey == i))
+		     pTab->iAutoIncPKey == (int) i))
 			continue;	/* This column is allowed to be NULL */
 
 		on_error = table_column_nullable_action(pTab, i);
@@ -1179,7 +1172,7 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 		else
 			on_error = ON_CONFLICT_ACTION_ABORT;
 
-		for (i = 0; i < checks->nExpr; i++) {
+		for (int i = 0; i < checks->nExpr; i++) {
 			int allOk;
 			Expr *pExpr = checks->a[i].pExpr;
 			if (aiChng
@@ -1206,13 +1199,16 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 		}
 	}
 
-	/* Test all UNIQUE constraints by creating entries for each UNIQUE
-	 * index and making sure that duplicate entries do not already exist.
-	 * Compute the revised record entries for indices as we go.
+	/*
+	 * Test all UNIQUE constraints by creating entries for
+	 * each UNIQUE index and making sure that duplicate entries
+	 * do not already exist. Compute the revised record entries
+	 * for indices as we go.
 	 *
 	 * This loop also handles the case of the PRIMARY KEY index.
 	 */
-	for (ix = 0, pIdx = pTab->pIndex; pIdx; pIdx = pIdx->pNext, ix++) {
+	pIdx = pTab->pIndex;
+	for (int ix = 0; pIdx != NULL; pIdx = pIdx->pNext, ix++) {
 		int regIdx;	/* Range of registers hold conent for pIdx */
 		int regR;	/* Range of registers holding conflicting PK */
 		int iThisCur;	/* Cursor for this UNIQUE index */
@@ -1253,10 +1249,11 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 		 * the insert or update.  Store that record in the aRegIdx[ix] register
 		 */
 		regIdx = aRegIdx[ix] + 1;
-		int nIdxCol = (int) index_column_count(pIdx);
+		uint32_t part_count = pIdx->def->key_def->part_count;
 		if (uniqueByteCodeNeeded) {
-			for (i = 0; i < nIdxCol; ++i) {
-				int fieldno = pIdx->aiColumn[i];
+			for (uint32_t i = 0; i < part_count; ++i) {
+				uint32_t fieldno =
+					pIdx->def->key_def->parts[i].fieldno;
 				int reg;
 				/*
 				 * OP_SCopy copies value in
@@ -1267,11 +1264,10 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 				 * needed for proper UNIQUE
 				 * constraint handling.
 				 */
-				if (fieldno == pTab->iPKey)
+				if ((int) fieldno == pTab->iPKey)
 					reg = regNewData;
 				else
 					reg = fieldno + regNewData + 1;
-				assert(fieldno >= 0);
 				sqlite3VdbeAddOp2(v, OP_SCopy, reg, regIdx + i);
 				VdbeComment((v, "%s",
 					    def->fields[fieldno].name));
@@ -1283,9 +1279,12 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 		if (IsPrimaryKeyIndex(pIdx)) {
 			/* If PK is marked as INTEGER, use it as strict type,
 			 * not as affinity. Emit code for type checking */
-			if (nIdxCol == 1) {
-				reg_pk = regNewData + 1 + pIdx->aiColumn[0];
-				if (pTab->zColAff[pIdx->aiColumn[0]] ==
+			if (part_count == 1) {
+				uint32_t fieldno =
+					pIdx->def->key_def->parts[0].fieldno;
+				reg_pk = regNewData + 1 + fieldno;
+
+				if (pTab->zColAff[fieldno] ==
 				    AFFINITY_INTEGER) {
 					int skip_if_null = sqlite3VdbeMakeLabel(v);
 					if ((pTab->tabFlags & TF_Autoincrement) != 0) {
@@ -1303,7 +1302,7 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 
 			sqlite3VdbeAddOp3(v, OP_MakeRecord, regNewData + 1,
 					  def->field_count, aRegIdx[ix]);
-			VdbeComment((v, "for %s", pIdx->zName));
+			VdbeComment((v, "for %s", pIdx->def->name));
 		}
 
 		/* In an UPDATE operation, if this index is the PRIMARY KEY
@@ -1390,24 +1389,22 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 		if (uniqueByteCodeNeeded) {
 			sqlite3VdbeAddOp4Int(v, OP_NoConflict, iThisCur,
 					     addrUniqueOk, regIdx,
-					     index_column_count(pIdx));
+					     pIdx->def->key_def->part_count);
 		}
 		VdbeCoverage(v);
 
+		const uint32_t pk_part_count = pPk->def->key_def->part_count;
 		/* Generate code to handle collisions */
-		regR =
-		    (pIdx == pPk) ? regIdx : sqlite3GetTempRange(pParse,
-								 nPkField);
+		regR = pIdx == pPk ? regIdx :
+		       sqlite3GetTempRange(pParse, pk_part_count);
 		if (isUpdate || on_error == ON_CONFLICT_ACTION_REPLACE) {
 			int x;
-			int nPkCol = index_column_count(pPk);
 			/* Extract the PRIMARY KEY from the end of the index entry and
 			 * store it in registers regR..regR+nPk-1
 			 */
 			if (pIdx != pPk) {
-				for (i = 0; i < nPkCol; i++) {
-					assert(pPk->aiColumn[i] >= 0);
-					x = pPk->aiColumn[i];
+				for (uint32_t i = 0; i < pk_part_count; i++) {
+					x = pPk->def->key_def->parts[i].fieldno;
 					sqlite3VdbeAddOp3(v, OP_Column,
 							  iThisCur, x, regR + i);
 					VdbeComment((v, "%s.%s", def->name,
@@ -1422,22 +1419,25 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 				 * of the matched index row are different from the original PRIMARY
 				 * KEY values of this row before the update.
 				 */
-				int addrJump =
-					sqlite3VdbeCurrentAddr(v) + nPkCol;
+				int addrJump = sqlite3VdbeCurrentAddr(v) +
+					       pk_part_count;
 				int op = OP_Ne;
-				int regCmp = (IsPrimaryKeyIndex(pIdx) ?
-					      regIdx : regR);
-
-				for (i = 0; i < nPkCol; i++) {
-					uint32_t id;
-					char *p4 = (char *)sql_index_collation(pPk, i, &id);
-					x = pPk->aiColumn[i];
-					assert(x >= 0);
-					if (i == (nPkCol - 1)) {
+				int regCmp = IsPrimaryKeyIndex(pIdx) ?
+					     regIdx : regR;
+				struct key_part *part =
+					pPk->def->key_def->parts;
+				for (uint32_t i = 0; i < pk_part_count;
+				     ++i, ++part) {
+					char *p4 = (char *) part->coll;
+					x = part->fieldno;
+					if (pPk->tnum==0)
+						x = -1;
+					if (i == (pk_part_count - 1)) {
 						addrJump = addrUniqueOk;
 						op = OP_Eq;
 					}
-					sqlite3VdbeAddOp4(v, op, regOldData + 1 + x,
+					sqlite3VdbeAddOp4(v, op,
+							  regOldData + 1 + x,
 							  addrJump, regCmp + i,
 							  p4, P4_COLLSEQ);
 					sqlite3VdbeChangeP5(v, SQLITE_NOTNULL);
@@ -1480,7 +1480,8 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 							      NULL, NULL);
 			}
 			sql_generate_row_delete(pParse, pTab, trigger,
-						iDataCur, regR, nPkField, false,
+						iDataCur, regR, pk_part_count,
+						false,
 						ON_CONFLICT_ACTION_REPLACE,
 						pIdx == pPk ? ONEPASS_SINGLE :
 						ONEPASS_OFF, -1);
@@ -1490,7 +1491,7 @@ sqlite3GenerateConstraintChecks(Parse * pParse,		/* The parser context */
 		}
 		sqlite3VdbeResolveLabel(v, addrUniqueOk);
 		if (regR != regIdx)
-			sqlite3ReleaseTempRange(pParse, regR, nPkField);
+			sqlite3ReleaseTempRange(pParse, regR, pk_part_count);
 	}
 
 	*pbMayReplace = seenReplace;
@@ -1608,8 +1609,8 @@ sqlite3OpenTableAndIndices(Parse * pParse,	/* Parsing context */
 		    IsPrimaryKeyIndex(pIdx) ||		/* Condition 2 */
 		    sqlite3FkReferences(pTab) ||	/* Condition 3 */
 		    /* Condition 4 */
-		    (index_is_unique(pIdx) && pIdx->onError !=
-		     ON_CONFLICT_ACTION_DEFAULT &&
+		    (pIdx->def->opts.is_unique &&
+		     pIdx->onError != ON_CONFLICT_ACTION_DEFAULT &&
 		     /* Condition 4.1 */
 		     pIdx->onError != ON_CONFLICT_ACTION_ABORT) ||
 		     /* Condition 4.2 */
@@ -1627,7 +1628,7 @@ sqlite3OpenTableAndIndices(Parse * pParse,	/* Parsing context */
 						  space_ptr_reg);
 				sql_vdbe_set_p4_key_def(pParse, pIdx);
 				sqlite3VdbeChangeP5(v, p5);
-				VdbeComment((v, "%s", pIdx->zName));
+				VdbeComment((v, "%s", pIdx->def->name));
 			}
 		}
 	}
@@ -1661,30 +1662,25 @@ int sqlite3_xferopt_count;
 static int
 xferCompatibleIndex(Index * pDest, Index * pSrc)
 {
-	uint32_t i;
 	assert(pDest && pSrc);
 	assert(pDest->pTable != pSrc->pTable);
-	uint32_t nDestCol = index_column_count(pDest);
-	uint32_t nSrcCol = index_column_count(pSrc);
-	if (nDestCol != nSrcCol) {
-		return 0;	/* Different number of columns */
-	}
+	uint32_t dest_idx_part_count = pDest->def->key_def->part_count;
+	uint32_t src_idx_part_count = pSrc->def->key_def->part_count;
+	if (dest_idx_part_count != src_idx_part_count)
+		return 0;
 	if (pDest->onError != pSrc->onError) {
 		return 0;	/* Different conflict resolution strategies */
 	}
-	for (i = 0; i < nSrcCol; i++) {
-		if (pSrc->aiColumn[i] != pDest->aiColumn[i]) {
+	struct key_part *src_part = pSrc->def->key_def->parts;
+	struct key_part *dest_part = pDest->def->key_def->parts;
+	for (uint32_t i = 0; i < src_idx_part_count;
+	     ++i, ++src_part, ++dest_part) {
+		if (src_part->fieldno != dest_part->fieldno)
 			return 0;	/* Different columns indexed */
-		}
-		if (sql_index_column_sort_order(pSrc, i) !=
-		    sql_index_column_sort_order(pDest, i)) {
+		if (src_part->sort_order != dest_part->sort_order)
 			return 0;	/* Different sort orders */
-		}
-		uint32_t id;
-		if (sql_index_collation(pSrc, i, &id) !=
-		    sql_index_collation(pDest, i, &id)) {
+		if (src_part->coll != dest_part->coll)
 			return 0;	/* Different collating sequences */
-		}
 	}
 	if (sqlite3ExprCompare(pSrc->pPartIdxWhere, pDest->pPartIdxWhere, -1)) {
 		return 0;	/* Different WHERE clauses */
@@ -1856,16 +1852,15 @@ xferOptimization(Parse * pParse,	/* Parser context */
 		}
 	}
 	for (pDestIdx = pDest->pIndex; pDestIdx; pDestIdx = pDestIdx->pNext) {
-		if (index_is_unique(pDestIdx)) {
+		if (pDestIdx->def->opts.is_unique)
 			destHasUniqueIdx = 1;
-		}
 		for (pSrcIdx = pSrc->pIndex; pSrcIdx; pSrcIdx = pSrcIdx->pNext) {
 			if (xferCompatibleIndex(pDestIdx, pSrcIdx))
 				break;
 		}
-		if (pSrcIdx == 0) {
-			return 0;	/* pDestIdx has no corresponding index in pSrc */
-		}
+		/* pDestIdx has no corresponding index in pSrc. */
+		if (pSrcIdx == NULL)
+			return 0;
 	}
 	/* Get server checks. */
 	ExprList *pCheck_src = space_checks_expr_list(
@@ -1941,11 +1936,11 @@ xferOptimization(Parse * pParse,	/* Parser context */
 		struct space *src_space =
 			space_by_id(SQLITE_PAGENO_TO_SPACEID(pSrcIdx->tnum));
 		vdbe_emit_open_cursor(pParse, iSrc, pSrcIdx->tnum, src_space);
-		VdbeComment((v, "%s", pSrcIdx->zName));
+		VdbeComment((v, "%s", pSrcIdx->def->name));
 		struct space *dest_space =
 			space_by_id(SQLITE_PAGENO_TO_SPACEID(pDestIdx->tnum));
 		vdbe_emit_open_cursor(pParse, iDest, pDestIdx->tnum, dest_space);
-		VdbeComment((v, "%s", pDestIdx->zName));
+		VdbeComment((v, "%s", pDestIdx->def->name));
 		addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0);
 		VdbeCoverage(v);
 		sqlite3VdbeAddOp2(v, OP_RowData, iSrc, regData);
diff --git a/src/box/sql/pragma.c b/src/box/sql/pragma.c
index be6a01c23..db0b9a482 100644
--- a/src/box/sql/pragma.c
+++ b/src/box/sql/pragma.c
@@ -369,9 +369,8 @@ sqlite3Pragma(Parse * pParse, Token * pId,	/* First part of [schema.]id field */
 			} else if (pk == NULL) {
 				k = 1;
 			} else {
-				for (k = 1; k <= def->field_count &&
-				     pk->aiColumn[k - 1] != (int) i; ++k) {
-				}
+				struct key_def *kdef = pk->def->key_def;
+				k = key_def_find(kdef, i) - kdef->parts + 1;
 			}
 			bool is_nullable = def->fields[i].is_nullable;
 			char *expr_str = def->fields[i].default_value;
@@ -414,7 +413,7 @@ sqlite3Pragma(Parse * pParse, Token * pId,	/* First part of [schema.]id field */
 					size_t avg_tuple_size_idx =
 						sql_index_tuple_size(space, idx);
 					sqlite3VdbeMultiLoad(v, 2, "sii",
-							     pIdx->zName,
+							     pIdx->def->name,
 							     avg_tuple_size_idx,
 							     index_field_tuple_est(pIdx, 0));
 					sqlite3VdbeAddOp2(v, OP_ResultRow, 1,
@@ -443,11 +442,13 @@ sqlite3Pragma(Parse * pParse, Token * pId,	/* First part of [schema.]id field */
 						 */
 						pParse->nMem = 3;
 					}
-					mx = index_column_count(pIdx);
+					mx = pIdx->def->key_def->part_count;
 					assert(pParse->nMem <=
 					       pPragma->nPragCName);
-					for (i = 0; i < mx; i++) {
-						i16 cnum = pIdx->aiColumn[i];
+					struct key_part *part =
+						pIdx->def->key_def->parts;
+					for (i = 0; i < mx; i++, part++) {
+						i16 cnum = (int) part->fieldno;
 						assert(pIdx->pTable);
 						sqlite3VdbeMultiLoad(v, 1,
 								     "iis", i,
@@ -461,19 +462,18 @@ sqlite3Pragma(Parse * pParse, Token * pId,	/* First part of [schema.]id field */
 								     name);
 						if (pPragma->iArg) {
 							const char *c_n;
-							uint32_t id;
+							uint32_t id =
+								part->coll_id;
 							struct coll *coll =
-								sql_index_collation(pIdx, i, &id);
+								part->coll;
 							if (coll != NULL)
 								c_n = coll_by_id(id)->name;
 							else
 								c_n = "BINARY";
-							enum sort_order sort_order;
-							sort_order = sql_index_column_sort_order(pIdx,
-												 i);
 							sqlite3VdbeMultiLoad(v,
 									     4,
 									     "isi",
+									     part->
 									     sort_order,
 									     c_n,
 									     i <
@@ -503,10 +503,8 @@ sqlite3Pragma(Parse * pParse, Token * pId,	/* First part of [schema.]id field */
 						    { "c", "u", "pk" };
 						sqlite3VdbeMultiLoad(v, 1,
 								     "isisi", i,
-								     pIdx->
-								     zName,
-								     index_is_unique
-								     (pIdx),
+								     pIdx->def->name,
+								     pIdx->def->opts.is_unique,
 								     azOrigin
 								     [pIdx->
 								      idxType],
diff --git a/src/box/sql/select.c b/src/box/sql/select.c
index 54f78a9de..adf10feca 100644
--- a/src/box/sql/select.c
+++ b/src/box/sql/select.c
@@ -4366,7 +4366,7 @@ sqlite3IndexedByLookup(Parse * pParse, struct SrcList_item *pFrom)
 		char *zIndexedBy = pFrom->u1.zIndexedBy;
 		Index *pIdx;
 		for (pIdx = pTab->pIndex;
-		     pIdx && strcmp(pIdx->zName, zIndexedBy);
+		     pIdx && strcmp(pIdx->def->name, zIndexedBy);
 		     pIdx = pIdx->pNext) ;
 		if (!pIdx) {
 			sqlite3ErrorMsg(pParse, "no such index: %s", zIndexedBy,
diff --git a/src/box/sql/sqliteInt.h b/src/box/sql/sqliteInt.h
index e939663b6..3a560f1db 100644
--- a/src/box/sql/sqliteInt.h
+++ b/src/box/sql/sqliteInt.h
@@ -2051,28 +2051,6 @@ struct UnpackedRecord {
  * Each SQL index is represented in memory by an
  * instance of the following structure.
  *
- * The columns of the table that are to be indexed are described
- * by the aiColumn[] field of this structure.  For example, suppose
- * we have the following table and index:
- *
- *     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
- *     CREATE INDEX Ex2 ON Ex1(c3,c1);
- *
- * In the Table structure describing Ex1, nCol==3 because there are
- * three columns in the table.  In the Index structure describing
- * Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
- * The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
- * first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
- * The second column to be indexed (c1) has an index of 0 in
- * Ex1.aCol[], hence Ex2.aiColumn[1]==0.
- *
- * The Index.onError field determines whether or not the indexed columns
- * must be unique and what to do if they are not.  When Index.onError=
- * ON_CONFLICT_ACTION_NONE, it means this is not a unique index.
- * Otherwise it is a unique index and the value of Index.onError indicate
- * the which conflict resolution algorithm to employ whenever an attempt
- * is made to insert a non-unique element.
- *
  * While parsing a CREATE TABLE or CREATE INDEX statement in order to
  * generate VDBE code (as opposed to reading from Tarantool's _space
  * space as part of parsing an existing database schema), transient instances
@@ -2082,26 +2060,30 @@ struct UnpackedRecord {
  * program is executed). See convertToWithoutRowidTable() for details.
  */
 struct Index {
-	char *zName;		/* Name of this index */
-	i16 *aiColumn;		/* Which columns are used by this index.  1st is 0 */
-	LogEst *aiRowLogEst;	/* From ANALYZE: Est. rows selected by each column */
-	Table *pTable;		/* The SQL table being indexed */
-	char *zColAff;		/* String defining the affinity of each column */
-	Index *pNext;		/* The next index associated with the same table */
-	Schema *pSchema;	/* Schema containing this index */
-	/** Sorting order for each column. */
-	enum sort_order *sort_order;
-	/** Array of collation sequences for index. */
-	struct coll **coll_array;
-	/** Array of collation identifiers. */
-	uint32_t *coll_id_array;
-	Expr *pPartIdxWhere;	/* WHERE clause for partial indices */
-	int tnum;		/* DB Page containing root of this index */
-	u16 nColumn;		/* Number of columns stored in the index */
-	u8 onError;		/* ON_CONFLICT_ACTION_ABORT, _IGNORE, _REPLACE,
-				 * or _NONE
-				 */
-	unsigned idxType:2;	/* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
+	/** From ANALYZE: Est. rows selected by each column. */
+	LogEst *aiRowLogEst;
+	/** The SQL table being indexed. */
+	Table *pTable;
+	/** String defining the affinity of each column. */
+	char *zColAff;
+	/** The next index associated with the same table. */
+	Index *pNext;
+	/** Schema containing this index. */
+	Schema *pSchema;
+	/** WHERE clause for partial indices. */
+	Expr *pPartIdxWhere;
+	/** DB Page containing root of this index. */
+	int tnum;
+	/**
+	 * Conflict resolution algorithm to employ whenever an
+	 * attempt is made to insert a non-unique element in
+	 * unique index.
+	 */
+	u8 onError;
+	/** 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX. */
+	unsigned idxType:2;
+	/** Index definition. */
+	struct index_def *def;
 };
 
 /**
@@ -3532,34 +3514,6 @@ void sqlite3AddCollateType(Parse *, Token *);
  */
 struct coll *
 sql_column_collation(struct space_def *def, uint32_t column, uint32_t *coll_id);
-/**
- * Return name of given column collation from index.
- *
- * @param idx Index which is used to fetch column.
- * @param column Number of column.
- * @param[out] coll_id Collation identifier.
- * @retval Pointer to collation.
- */
-struct coll *
-sql_index_collation(Index *idx, uint32_t column, uint32_t *id);
-
-/**
- * Return key_def of provided struct Index.
- * @param idx Pointer to `struct Index` object.
- * @retval Pointer to `struct key_def`.
- */
-struct key_def*
-sql_index_key_def(struct Index *idx);
-
-/**
- * Return sort order of given column from index.
- *
- * @param idx Index which is used to fetch column.
- * @param column Number of column.
- * @retval Sort order of requested column.
- */
-enum sort_order
-sql_index_column_sort_order(Index *idx, uint32_t column);
 
 void sqlite3EndTable(Parse *, Token *, Token *, Select *);
 
@@ -3646,9 +3600,16 @@ void sqlite3SrcListShiftJoinType(SrcList *);
 void sqlite3SrcListAssignCursors(Parse *, SrcList *);
 void sqlite3IdListDelete(sqlite3 *, IdList *);
 void sqlite3SrcListDelete(sqlite3 *, SrcList *);
-Index *sqlite3AllocateIndexObject(sqlite3 *, i16, int, char **);
-bool
-index_is_unique(Index *);
+/**
+ * Allocate SQL index object with part count fields.
+ * @param db SQLite environment.
+ * @param part_count Index part_count.
+ *
+ * @retval NULL Memory error.
+ * @retval not NULL Index object.
+ */
+struct Index *
+sql_index_alloc(struct sqlite3 *db, uint32_t part_count);
 
 /**
  * Create a new index for an SQL table.  name is the name of the
@@ -3678,8 +3639,9 @@ index_is_unique(Index *);
 void
 sql_create_index(struct Parse *parse, struct Token *token,
 		 struct SrcList *tbl_name, struct ExprList *col_list,
-		 int on_error, struct Token *start, struct Expr *pi_where,
-		 enum sort_order sort_order, bool if_not_exist, u8 idx_type);
+		 enum on_conflict_action on_error, struct Token *start,
+		 struct Expr *pi_where, enum sort_order sort_order,
+		 bool if_not_exist, u8 idx_type);
 
 /**
  * This routine will drop an existing named index.  This routine
@@ -4531,10 +4493,6 @@ int sqlite3InvokeBusyHandler(BusyHandler *);
 int
 sql_analysis_load(struct sqlite3 *db);
 
-uint32_t
-index_column_count(const Index *);
-bool
-index_is_unique_not_null(const Index *);
 void sqlite3RegisterLikeFunctions(sqlite3 *, int);
 int sqlite3IsLikeFunction(sqlite3 *, Expr *, int *, char *);
 void sqlite3SchemaClear(sqlite3 *);
diff --git a/src/box/sql/update.c b/src/box/sql/update.c
index 212adbcb3..113e3ba0e 100644
--- a/src/box/sql/update.c
+++ b/src/box/sql/update.c
@@ -239,17 +239,18 @@ sqlite3Update(Parse * pParse,		/* The parser context */
 	 */
 	for (j = 0, pIdx = pTab->pIndex; pIdx; pIdx = pIdx->pNext, j++) {
 		int reg;
-		int nIdxCol = index_column_count(pIdx);
+		uint32_t part_count = pIdx->def->key_def->part_count;
 		if (chngPk || hasFK || pIdx->pPartIdxWhere || pIdx == pPk) {
 			reg = ++pParse->nMem;
-			pParse->nMem += nIdxCol;
+			pParse->nMem += part_count;
 		} else {
 			reg = 0;
-			for (i = 0; i < nIdxCol; i++) {
-				i16 iIdxCol = pIdx->aiColumn[i];
-				if (iIdxCol < 0 || aXRef[iIdxCol] >= 0) {
+			for (uint32_t i = 0; i < part_count; i++) {
+				uint32_t fieldno =
+					pIdx->def->key_def->parts[i].fieldno;
+				if (aXRef[fieldno] >= 0) {
 					reg = ++pParse->nMem;
-					pParse->nMem += nIdxCol;
+					pParse->nMem += part_count;
 					break;
 				}
 			}
@@ -299,17 +300,18 @@ sqlite3Update(Parse * pParse,		/* The parser context */
 	 * In this case we have to manually load columns in order to make tuple.
 	 */
 	int iPk;	/* First of nPk memory cells holding PRIMARY KEY value */
-	i16 nPk;	/* Number of components of the PRIMARY KEY */
+	/* Number of components of the PRIMARY KEY.  */
+	uint32_t pk_part_count;
 	int addrOpen;	/* Address of the OpenEphemeral instruction */
 
 	if (is_view) {
-		nPk = nKey;
+		pk_part_count = nKey;
 	} else {
 		assert(pPk != 0);
-		nPk = index_column_count(pPk);
+		pk_part_count = pPk->def->key_def->part_count;
 	}
 	iPk = pParse->nMem + 1;
-	pParse->nMem += nPk;
+	pParse->nMem += pk_part_count;
 	regKey = ++pParse->nMem;
 	iEph = pParse->nTab++;
 	sqlite3VdbeAddOp2(v, OP_Null, 0, iPk);
@@ -318,7 +320,8 @@ sqlite3Update(Parse * pParse,		/* The parser context */
 		addrOpen = sqlite3VdbeAddOp2(v, OP_OpenTEphemeral, iEph,
 					     nKey);
 	} else {
-		addrOpen = sqlite3VdbeAddOp2(v, OP_OpenTEphemeral, iEph, nPk);
+		addrOpen = sqlite3VdbeAddOp2(v, OP_OpenTEphemeral, iEph,
+					     pk_part_count);
 		sql_vdbe_set_p4_key_def(pParse, pPk);
 	}
 
@@ -328,27 +331,27 @@ sqlite3Update(Parse * pParse,		/* The parser context */
 		goto update_cleanup;
 	okOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
 	if (is_view) {
-		for (i = 0; i < nPk; i++) {
+		for (i = 0; i < (int) pk_part_count; i++) {
 			sqlite3VdbeAddOp3(v, OP_Column, iDataCur, i, iPk + i);
 		}
 	} else {
-		for (i = 0; i < nPk; i++) {
-			assert(pPk->aiColumn[i] >= 0);
+		for (i = 0; i < (int) pk_part_count; i++) {
 			sqlite3ExprCodeGetColumnOfTable(v, def, iDataCur,
-							pPk->aiColumn[i],
+							pPk->def->key_def->
+								parts[i].fieldno,
 							iPk + i);
 		}
 	}
 
 	if (okOnePass) {
 		sqlite3VdbeChangeToNoop(v, addrOpen);
-		nKey = nPk;
+		nKey = pk_part_count;
 		regKey = iPk;
 	} else {
 		const char *zAff = is_view ? 0 :
 				   sqlite3IndexAffinityStr(pParse->db, pPk);
-		sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, regKey,
-					  zAff, nPk);
+		sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, pk_part_count,
+				  regKey, zAff, pk_part_count);
 		sqlite3VdbeAddOp2(v, OP_IdxInsert, iEph, regKey);
 		/* Set flag to save memory allocating one by malloc. */
 		sqlite3VdbeChangeP5(v, 1);
diff --git a/src/box/sql/vdbeaux.c b/src/box/sql/vdbeaux.c
index a8bd1e582..e50a23b3d 100644
--- a/src/box/sql/vdbeaux.c
+++ b/src/box/sql/vdbeaux.c
@@ -1150,7 +1150,7 @@ sql_vdbe_set_p4_key_def(struct Parse *parse, struct Index *idx)
 	struct Vdbe *v = parse->pVdbe;
 	assert(v != NULL);
 	assert(idx != NULL);
-	struct key_def *def = key_def_dup(sql_index_key_def(idx));
+	struct key_def *def = key_def_dup(idx->def->key_def);
 	if (def == NULL)
 		sqlite3OomFault(parse->db);
 	else
diff --git a/src/box/sql/vdbemem.c b/src/box/sql/vdbemem.c
index 2ce90747d..d0e16bafb 100644
--- a/src/box/sql/vdbemem.c
+++ b/src/box/sql/vdbemem.c
@@ -1087,15 +1087,15 @@ valueNew(sqlite3 * db, struct ValueNewStat4Ctx *p)
 			Index *pIdx = p->pIdx;	/* Index being probed */
 			int nByte;	/* Bytes of space to allocate */
 			int i;	/* Counter variable */
-			int nCol = index_column_count(pIdx);
+			int part_count = pIdx->def->key_def->part_count;
 
-			nByte = sizeof(Mem) * nCol +
+			nByte = sizeof(Mem) * part_count +
 				ROUND8(sizeof(UnpackedRecord));
 			pRec =
 			    (UnpackedRecord *) sqlite3DbMallocZero(db, nByte);
 			if (pRec == NULL)
 				return NULL;
-			pRec->key_def = key_def_dup(sql_index_key_def(pIdx));
+			pRec->key_def = key_def_dup(pIdx->def->key_def);
 			if (pRec->key_def == NULL) {
 				sqlite3DbFree(db, pRec);
 				sqlite3OomFault(db);
@@ -1103,7 +1103,7 @@ valueNew(sqlite3 * db, struct ValueNewStat4Ctx *p)
 			}
 			pRec->aMem = (Mem *)((char *) pRec +
 					     ROUND8(sizeof(UnpackedRecord)));
-			for (i = 0; i < nCol; i++) {
+			for (i = 0; i < (int) part_count; i++) {
 				pRec->aMem[i].flags = MEM_Null;
 				pRec->aMem[i].db = db;
 			}
@@ -1621,15 +1621,12 @@ sql_stat4_column(struct sqlite3 *db, const char *record, uint32_t col_num,
 void
 sqlite3Stat4ProbeFree(UnpackedRecord * pRec)
 {
-	if (pRec) {
-		int i;
-		int nCol = pRec->key_def->part_count;
-		Mem *aMem = pRec->aMem;
-		sqlite3 *db = aMem[0].db;
-		for (i = 0; i < nCol; i++) {
+	if (pRec != NULL) {
+		int part_count = pRec->key_def->part_count;
+		struct Mem *aMem = pRec->aMem;
+		for (int i = 0; i < part_count; i++)
 			sqlite3VdbeMemRelease(&aMem[i]);
-		}
-		sqlite3DbFree(db, pRec);
+		sqlite3DbFree(aMem[0].db, pRec);
 	}
 }
 
diff --git a/src/box/sql/where.c b/src/box/sql/where.c
index 85143ed20..7ca02095f 100644
--- a/src/box/sql/where.c
+++ b/src/box/sql/where.c
@@ -372,13 +372,19 @@ whereScanInit(WhereScan * pScan,	/* The WhereScan object being initialized */
 	pScan->is_column_seen = false;
 	if (pIdx) {
 		int j = iColumn;
-		iColumn = pIdx->aiColumn[j];
+		iColumn = pIdx->def->key_def->parts[j].fieldno;
+		/*
+		 * pIdx->tnum == 0 means that pIdx is a fake
+		 * integer primary key index.
+		 */
+		if (pIdx->tnum == 0)
+			iColumn = -1;
+
 		if (iColumn >= 0) {
 			char affinity =
 				pIdx->pTable->def->fields[iColumn].affinity;
 			pScan->idxaff = affinity;
-			uint32_t id;
-			pScan->coll = sql_index_collation(pIdx, j, &id);
+			pScan->coll = pIdx->def->key_def->parts[j].coll;
 			pScan->is_column_seen = true;
 		}
 	}
@@ -541,47 +547,24 @@ findIndexCol(Parse * pParse,	/* Parse context */
 	     Index * pIdx,	/* Index to match column of */
 	     int iCol)		/* Column of index to match */
 {
+	struct key_part *part_to_match = &pIdx->def->key_def->parts[iCol];
 	for (int i = 0; i < pList->nExpr; i++) {
 		Expr *p = sqlite3ExprSkipCollate(pList->a[i].pExpr);
-		if (p->op == TK_COLUMN &&
-		    p->iColumn == pIdx->aiColumn[iCol] &&
-		    p->iTable == iBase) {
+		if (p->op == TK_COLUMN && p->iTable == iBase &&
+		    p->iColumn == (int) part_to_match->fieldno) {
 			bool is_found;
 			uint32_t id;
 			struct coll *coll = sql_expr_coll(pParse,
 							  pList->a[i].pExpr,
 							  &is_found, &id);
-			if (is_found &&
-			    coll == sql_index_collation(pIdx, iCol, &id)) {
+			if (is_found && coll == part_to_match->coll)
 				return i;
-			}
 		}
 	}
 
 	return -1;
 }
 
-/*
- * Return TRUE if the iCol-th column of index pIdx is NOT NULL
- */
-static int
-indexColumnNotNull(Index * pIdx, int iCol)
-{
-	int j;
-	assert(pIdx != 0);
-	assert(iCol >= 0 && iCol < (int)index_column_count(pIdx));
-	j = pIdx->aiColumn[iCol];
-	if (j >= 0) {
-		return !pIdx->pTable->def->fields[j].is_nullable;
-	} else if (j == (-1)) {
-		return 1;
-	} else {
-		assert(j == (-2));
-		return 0;	/* Assume an indexed expression can always yield a NULL */
-
-	}
-}
-
 /*
  * Return true if the DISTINCT expression-list passed as the third argument
  * is redundant.
@@ -633,9 +616,9 @@ isDistinctRedundant(Parse * pParse,		/* Parsing context */
 	 *      contain a "col=X" term are subject to a NOT NULL constraint.
 	 */
 	for (pIdx = pTab->pIndex; pIdx; pIdx = pIdx->pNext) {
-		if (!index_is_unique(pIdx))
+		if (!pIdx->def->opts.is_unique)
 			continue;
-		int col_count = index_column_count(pIdx);
+		int col_count = pIdx->def->key_def->part_count;
 		for (i = 0; i < col_count; i++) {
 			if (0 ==
 			    sqlite3WhereFindTerm(pWC, iBase, i, ~(Bitmask) 0,
@@ -643,11 +626,12 @@ isDistinctRedundant(Parse * pParse,		/* Parsing context */
 				if (findIndexCol
 				    (pParse, pDistinct, iBase, pIdx, i) < 0)
 					break;
-				if (indexColumnNotNull(pIdx, i) == 0)
+				uint32_t j = pIdx->def->key_def->parts[i].fieldno;
+				if (pIdx->pTable->def->fields[j].is_nullable)
 					break;
 			}
 		}
-		if (i == (int)index_column_count(pIdx)) {
+		if (i == (int) pIdx->def->key_def->part_count) {
 			/* This index implies that the DISTINCT qualifier is redundant. */
 			return 1;
 		}
@@ -835,8 +819,7 @@ constructAutomaticIndex(Parse * pParse,			/* The parsing context */
 	}
 
 	/* Construct the Index object to describe this index */
-	pIdx =
-	    sqlite3AllocateIndexObject(pParse->db, nKeyCol + 1, 0, &zNotUsed);
+	pIdx = sql_index_alloc(pParse->db, nKeyCol + 1);
 	if (pIdx == 0)
 		goto end_auto_index_create;
 	pLoop->pIndex = pIdx;
@@ -1184,7 +1167,7 @@ whereRangeAdjust(WhereTerm * pTerm, LogEst nNew)
 char
 sqlite3IndexColumnAffinity(sqlite3 * db, Index * pIdx, int iCol)
 {
-	assert(iCol >= 0 && iCol < (int)index_column_count(pIdx));
+	assert(iCol >= 0 && iCol < (int) pIdx->def->key_def->part_count);
 	if (!pIdx->zColAff) {
 		if (sqlite3IndexAffinityStr(db, pIdx) == 0)
 			return AFFINITY_BLOB;
@@ -1246,13 +1229,12 @@ whereRangeSkipScanEst(Parse * pParse,		/* Parsing & code generating context */
 	int nUpper = index->def->opts.stat->sample_count + 1;
 	int rc = SQLITE_OK;
 	u8 aff = sqlite3IndexColumnAffinity(db, p, nEq);
-	uint32_t id;
 
 	sqlite3_value *p1 = 0;	/* Value extracted from pLower */
 	sqlite3_value *p2 = 0;	/* Value extracted from pUpper */
 	sqlite3_value *pVal = 0;	/* Value extracted from record */
 
-	struct coll *pColl = sql_index_collation(p, nEq, &id);
+	struct coll *coll = p->def->key_def->parts[nEq].coll;
 	if (pLower) {
 		rc = sqlite3Stat4ValueFromExpr(pParse, pLower->pExpr->pRight,
 					       aff, &p1);
@@ -1273,12 +1255,12 @@ whereRangeSkipScanEst(Parse * pParse,		/* Parsing & code generating context */
 			rc = sql_stat4_column(db, samples[i].sample_key, nEq,
 					      &pVal);
 			if (rc == SQLITE_OK && p1) {
-				int res = sqlite3MemCompare(p1, pVal, pColl);
+				int res = sqlite3MemCompare(p1, pVal, coll);
 				if (res >= 0)
 					nLower++;
 			}
 			if (rc == SQLITE_OK && p2) {
-				int res = sqlite3MemCompare(p2, pVal, pColl);
+				int res = sqlite3MemCompare(p2, pVal, coll);
 				if (res >= 0)
 					nUpper++;
 			}
@@ -1448,7 +1430,7 @@ whereRangeScanEst(Parse * pParse,	/* Parsing & code generating context */
 			       || (pLower->eOperator & (WO_GT | WO_GE)) != 0);
 			assert(pUpper == 0
 			       || (pUpper->eOperator & (WO_LT | WO_LE)) != 0);
-			if (sql_index_column_sort_order(p, nEq) !=
+			if (p->def->key_def->parts[nEq].sort_order !=
 			    SORT_ORDER_ASC) {
 				/* The roles of pLower and pUpper are swapped for a DESC index */
 				SWAP(pLower, pUpper);
@@ -1598,7 +1580,7 @@ whereEqualScanEst(Parse * pParse,	/* Parsing & code generating context */
 	int bOk;
 
 	assert(nEq >= 1);
-	assert(nEq <= (int)index_column_count(p));
+	assert(nEq <= (int) p->def->key_def->part_count);
 	assert(pBuilder->nRecValid < nEq);
 
 	/* If values are not available for all fields of the index to the left
@@ -1619,7 +1601,7 @@ whereEqualScanEst(Parse * pParse,	/* Parsing & code generating context */
 
 	whereKeyStats(pParse, p, pRec, 0, a);
 	WHERETRACE(0x10, ("equality scan regions %s(%d): %d\n",
-			  p->zName, nEq - 1, (int)a[1]));
+			  p->def->name, nEq - 1, (int)a[1]));
 	*pnRow = a[1];
 
 	return rc;
@@ -1751,7 +1733,7 @@ whereLoopPrint(WhereLoop * p, WhereClause * pWC)
 			   pItem->zAlias ? pItem->zAlias : pTab->def->name);
 #endif
 	const char *zName;
-	if (p->pIndex && (zName = p->pIndex->zName) != 0) {
+	if (p->pIndex != NULL && (zName = p->pIndex->def->name) != NULL) {
 		if (strncmp(zName, "sqlite_autoindex_", 17) == 0) {
 			int i = sqlite3Strlen30(zName) - 1;
 			while (zName[i] != '_')
@@ -2314,7 +2296,7 @@ whereRangeVectorLen(Parse * pParse,	/* Parsing context */
 	int nCmp = sqlite3ExprVectorSize(pTerm->pExpr->pLeft);
 	int i;
 
-	nCmp = MIN(nCmp, (int)(index_column_count(pIdx) - nEq));
+	nCmp = MIN(nCmp, (int)(pIdx->def->key_def->part_count - nEq));
 	for (i = 1; i < nCmp; i++) {
 		/* Test if comparison i of pTerm is compatible with column (i+nEq)
 		 * of the index. If not, exit the loop.
@@ -2335,13 +2317,11 @@ whereRangeVectorLen(Parse * pParse,	/* Parsing context */
 		 * order of the index column is the same as the sort order of the
 		 * leftmost index column.
 		 */
-		if (pLhs->op != TK_COLUMN
-		    || pLhs->iTable != iCur
-		    || pLhs->iColumn != pIdx->aiColumn[i + nEq]
-		    || sql_index_column_sort_order(pIdx, i + nEq) !=
-		       sql_index_column_sort_order(pIdx, nEq)) {
+		struct key_part *parts = pIdx->def->key_def->parts;
+		if (pLhs->op != TK_COLUMN || pLhs->iTable != iCur ||
+		    pLhs->iColumn != (int)parts[i + nEq].fieldno ||
+		    parts[i + nEq].sort_order != parts[nEq].sort_order)
 			break;
-		}
 
 		aff = sqlite3CompareAffinity(pRhs, sqlite3ExprAffinity(pLhs));
 		idxaff =
@@ -2353,7 +2333,7 @@ whereRangeVectorLen(Parse * pParse,	/* Parsing context */
 		pColl = sql_binary_compare_coll_seq(pParse, pLhs, pRhs, &id);
 		if (pColl == 0)
 			break;
-	        if (sql_index_collation(pIdx, i + nEq, &id) != pColl)
+		if (pIdx->def->key_def->parts[i + nEq].coll != pColl)
 			break;
 	}
 	return i;
@@ -2396,13 +2376,13 @@ whereLoopAddBtreeIndex(WhereLoopBuilder * pBuilder,	/* The WhereLoop factory */
 	LogEst rSize;		/* Number of rows in the table */
 	LogEst rLogSize;	/* Logarithm of table size */
 	WhereTerm *pTop = 0, *pBtm = 0;	/* Top and bottom range constraints */
-	uint32_t nProbeCol = index_column_count(pProbe);
+	uint32_t probe_part_count = pProbe->def->key_def->part_count;
 
 	pNew = pBuilder->pNew;
 	if (db->mallocFailed)
 		return SQLITE_NOMEM_BKPT;
 	WHERETRACE(0x800, ("BEGIN addBtreeIdx(%s), nEq=%d\n",
-			   pProbe->zName, pNew->nEq));
+			   pProbe->def->name, pNew->nEq));
 
 	assert((pNew->wsFlags & WHERE_TOP_LIMIT) == 0);
 	if (pNew->wsFlags & WHERE_BTM_LIMIT) {
@@ -2431,7 +2411,7 @@ whereLoopAddBtreeIndex(WhereLoopBuilder * pBuilder,	/* The WhereLoop factory */
 		stat = &surrogate_stat;
 	if (stat->is_unordered)
 		opMask &= ~(WO_GT | WO_GE | WO_LT | WO_LE);
-	assert(pNew->nEq < nProbeCol);
+	assert(pNew->nEq < probe_part_count);
 
 	saved_nEq = pNew->nEq;
 	saved_nBtm = pNew->nBtm;
@@ -2452,10 +2432,14 @@ whereLoopAddBtreeIndex(WhereLoopBuilder * pBuilder,	/* The WhereLoop factory */
 		LogEst nOutUnadjusted;	/* nOut before IN() and WHERE adjustments */
 		int nIn = 0;
 		int nRecValid = pBuilder->nRecValid;
-		if ((eOp == WO_ISNULL || (pTerm->wtFlags & TERM_VNULL) != 0)
-		    && indexColumnNotNull(pProbe, saved_nEq)
-		    ) {
-			continue;	/* ignore IS [NOT] NULL constraints on NOT NULL columns */
+		uint32_t j = pProbe->def->key_def->parts[saved_nEq].fieldno;
+		if ((eOp == WO_ISNULL || (pTerm->wtFlags & TERM_VNULL) != 0) &&
+		    !pProbe->pTable->def->fields[j].is_nullable) {
+			/*
+			 * Ignore IS [NOT] NULL constraints on NOT
+			 * NULL columns.
+			 */
+			continue;
 		}
 		if (pTerm->prereqRight & pNew->maskSelf)
 			continue;
@@ -2523,14 +2507,16 @@ whereLoopAddBtreeIndex(WhereLoopBuilder * pBuilder,	/* The WhereLoop factory */
 							 */
 			}
 		} else if (eOp & WO_EQ) {
-			int iCol = pProbe->aiColumn[saved_nEq];
+			int iCol = pProbe->def->key_def->parts[saved_nEq].fieldno;
 			pNew->wsFlags |= WHERE_COLUMN_EQ;
 			assert(saved_nEq == pNew->nEq);
-			if ((iCol > 0 && nInMul == 0
-				&& saved_nEq == nProbeCol - 1)
-			    ) {
-				if (iCol >= 0 &&
-				    !index_is_unique_not_null(pProbe)) {
+			if (iCol > 0 && nInMul == 0 &&
+			    saved_nEq == probe_part_count - 1) {
+				bool index_is_unique_not_null =
+					pProbe->def->key_def->is_nullable &&
+					pProbe->def->opts.is_unique;
+				if (pProbe->tnum != 0 &&
+				    !index_is_unique_not_null) {
 					pNew->wsFlags |= WHERE_UNQ_WANTED;
 				} else {
 					pNew->wsFlags |= WHERE_ONEROW;
@@ -2592,8 +2578,7 @@ whereLoopAddBtreeIndex(WhereLoopBuilder * pBuilder,	/* The WhereLoop factory */
 			assert(eOp & (WO_ISNULL | WO_EQ | WO_IN));
 
 			assert(pNew->nOut == saved_nOut);
-			if (pTerm->truthProb <= 0
-			    && pProbe->aiColumn[saved_nEq] >= 0) {
+			if (pTerm->truthProb <= 0 && pProbe->tnum != 0 ) {
 				assert((eOp & WO_IN) || nIn == 0);
 				testcase(eOp & WO_IN);
 				pNew->nOut += pTerm->truthProb;
@@ -2695,8 +2680,8 @@ whereLoopAddBtreeIndex(WhereLoopBuilder * pBuilder,	/* The WhereLoop factory */
 			pNew->nOut = nOutUnadjusted;
 		}
 
-		if ((pNew->wsFlags & WHERE_TOP_LIMIT) == 0
-		    && pNew->nEq < nProbeCol) {
+		if ((pNew->wsFlags & WHERE_TOP_LIMIT) == 0 &&
+		    pNew->nEq < probe_part_count) {
 			whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe,
 					       nInMul + nIn);
 		}
@@ -2724,7 +2709,7 @@ whereLoopAddBtreeIndex(WhereLoopBuilder * pBuilder,	/* The WhereLoop factory */
 	 * more expensive.
 	 */
 	assert(42 == sqlite3LogEst(18));
-	if (saved_nEq == saved_nSkip && saved_nEq + 1U < nProbeCol &&
+	if (saved_nEq == saved_nSkip && saved_nEq + 1U < probe_part_count &&
 	    stat->skip_scan_enabled == true &&
 	    /* TUNING: Minimum for skip-scan */
 	    index_field_tuple_est(pProbe, saved_nEq + 1) >= 42 &&
@@ -2749,7 +2734,7 @@ whereLoopAddBtreeIndex(WhereLoopBuilder * pBuilder,	/* The WhereLoop factory */
 	}
 
 	WHERETRACE(0x800, ("END addBtreeIdx(%s), nEq=%d, rc=%d\n",
-			   pProbe->zName, saved_nEq, rc));
+			   pProbe->def->name, saved_nEq, rc));
 	return rc;
 }
 
@@ -2792,7 +2777,7 @@ indexMightHelpWithOrderBy(WhereLoopBuilder * pBuilder,
 {
 	ExprList *pOB;
 	int ii, jj;
-	int nIdxCol = index_column_count(pIndex);
+	int part_count = pIndex->def->key_def->part_count;
 	if (index_is_unordered(pIndex))
 		return 0;
 	if ((pOB = pBuilder->pWInfo->pOrderBy) == 0)
@@ -2802,8 +2787,9 @@ indexMightHelpWithOrderBy(WhereLoopBuilder * pBuilder,
 		if (pExpr->op == TK_COLUMN && pExpr->iTable == iCursor) {
 			if (pExpr->iColumn < 0)
 				return 1;
-			for (jj = 0; jj < nIdxCol; jj++) {
-				if (pExpr->iColumn == pIndex->aiColumn[jj])
+			for (jj = 0; jj < part_count; jj++) {
+				if (pExpr->iColumn == (int)
+				    pIndex->def->key_def->parts[jj].fieldno)
 					return 1;
 			}
 		}
@@ -2882,7 +2868,6 @@ whereLoopAddBtree(WhereLoopBuilder * pBuilder,	/* WHERE clause information */
 	Index *pProbe;		/* An index we are evaluating */
 	Index sPk;		/* A fake index object for the primary key */
 	LogEst aiRowEstPk[2];	/* The aiRowLogEst[] value for the sPk index */
-	i16 aiColumnPk = -1;	/* The aColumn[] value for the sPk index */
 	SrcList *pTabList;	/* The FROM clause */
 	struct SrcList_item *pSrc;	/* The FROM clause btree term to add */
 	WhereLoop *pNew;	/* Template WhereLoop object */
@@ -2913,11 +2898,32 @@ whereLoopAddBtree(WhereLoopBuilder * pBuilder,	/* WHERE clause information */
 		 */
 		Index *pFirst;	/* First of real indices on the table */
 		memset(&sPk, 0, sizeof(Index));
-		sPk.nColumn = 1;
-		sPk.aiColumn = &aiColumnPk;
 		sPk.aiRowLogEst = aiRowEstPk;
 		sPk.onError = ON_CONFLICT_ACTION_REPLACE;
 		sPk.pTable = pTab;
+
+		struct key_def *key_def = key_def_new(1);
+		if (key_def == NULL) {
+			pWInfo->pParse->nErr++;
+			pWInfo->pParse->rc = SQL_TARANTOOL_ERROR;
+			return SQL_TARANTOOL_ERROR;
+		}
+
+		key_def_set_part(key_def, 0, 0, pTab->def->fields[0].type,
+				 ON_CONFLICT_ACTION_ABORT,
+				 NULL, COLL_NONE, SORT_ORDER_ASC);
+
+		sPk.def = index_def_new(pTab->def->id, 0, "primary",
+					sizeof("primary") - 1, TREE,
+					&index_opts_default, key_def, NULL);
+		key_def_delete(key_def);
+
+		if (sPk.def == NULL) {
+			pWInfo->pParse->nErr++;
+			pWInfo->pParse->rc = SQL_TARANTOOL_ERROR;
+			return SQL_TARANTOOL_ERROR;
+		}
+
 		aiRowEstPk[0] = sql_space_tuple_log_count(pTab);
 		aiRowEstPk[1] = 0;
 		pFirst = pSrc->pTab->pIndex;
@@ -3058,6 +3064,8 @@ whereLoopAddBtree(WhereLoopBuilder * pBuilder,	/* WHERE clause information */
 		if (pSrc->pIBIndex)
 			break;
 	}
+	if (&sPk == pProbe && sPk.def != NULL)
+		index_def_delete(sPk.def);
 	return rc;
 }
 
@@ -3392,8 +3400,8 @@ wherePathSatisfiesOrderBy(WhereInfo * pWInfo,	/* The WHERE clause */
 				   index_is_unordered(pIndex)) {
 				return 0;
 			} else {
-				nColumn = index_column_count(pIndex);
-				isOrderDistinct = index_is_unique(pIndex);
+				nColumn = pIndex->def->key_def->part_count;
+				isOrderDistinct = pIndex->def->opts.is_unique;
 			}
 
 			/* Loop through all columns of the index and deal with the ones
@@ -3454,9 +3462,10 @@ wherePathSatisfiesOrderBy(WhereInfo * pWInfo,	/* The WHERE clause */
 				 * (revIdx) for the j-th column of the index.
 				 */
 				if (pIndex != NULL) {
-					iColumn = pIndex->aiColumn[j];
-					revIdx = sql_index_column_sort_order(pIndex,
-									     j);
+					struct key_def *def =
+						pIndex->def->key_def;
+					iColumn = def->parts[j].fieldno;
+					revIdx = def->parts[j].sort_order;
 					if (iColumn == pIndex->pTable->iPKey)
 						iColumn = -1;
 				} else {
@@ -3506,8 +3515,7 @@ wherePathSatisfiesOrderBy(WhereInfo * pWInfo,	/* The WHERE clause */
 								      pOrderBy->a[i].pExpr,
 								      &is_found, &id);
 						struct coll *idx_coll =
-							sql_index_collation(pIndex,
-									    j, &id);
+							pIndex->def->key_def->parts[j].coll;
 						if (is_found &&
 						    coll != idx_coll)
 							continue;
@@ -4777,7 +4785,7 @@ sqlite3WhereBegin(Parse * pParse,	/* The parser context */
 					sqlite3VdbeChangeP5(v, OPFLAG_SEEKEQ);	/* Hint to COMDB2 */
 				}
 				if (pIx != NULL)
-					VdbeComment((v, "%s", pIx->zName));
+					VdbeComment((v, "%s", pIx->def->name));
 				else
 					VdbeComment((v, "%s", idx_def->name));
 #ifdef SQLITE_ENABLE_COLUMN_USED_MASK
@@ -4910,7 +4918,7 @@ sqlite3WhereEnd(WhereInfo * pWInfo)
 		if (pLevel->addrSkip) {
 			sqlite3VdbeGoto(v, pLevel->addrSkip);
 			VdbeComment((v, "next skip-scan on %s",
-				     pLoop->pIndex->zName));
+				     pLoop->pIndex->def->name));
 			sqlite3VdbeJumpHere(v, pLevel->addrSkip);
 			sqlite3VdbeJumpHere(v, pLevel->addrSkip - 2);
 		}
diff --git a/src/box/sql/wherecode.c b/src/box/sql/wherecode.c
index c35c25ac4..1976583fa 100644
--- a/src/box/sql/wherecode.c
+++ b/src/box/sql/wherecode.c
@@ -48,7 +48,7 @@
 static const char *
 explainIndexColumnName(Index * pIdx, int i)
 {
-	i = pIdx->aiColumn[i];
+	i = pIdx->def->key_def->parts[i].fieldno;
 	return pIdx->pTable->def->fields[i].name;
 }
 
@@ -243,7 +243,7 @@ sqlite3WhereExplainOneScan(Parse * pParse,	/* Parse context */
 			if (zFmt) {
 				sqlite3StrAccumAppend(&str, " USING ", 7);
 				if (pIdx != NULL)
-					sqlite3XPrintf(&str, zFmt, pIdx->zName);
+					sqlite3XPrintf(&str, zFmt, pIdx->def->name);
 				else if (idx_def != NULL)
 					sqlite3XPrintf(&str, zFmt, idx_def->name);
 				else
@@ -488,7 +488,7 @@ codeEqualityTerm(Parse * pParse,	/* The parsing context */
 		int *aiMap = 0;
 
 		if (pLoop->pIndex != 0 &&
-		    sql_index_column_sort_order(pLoop->pIndex, iEq)) {
+		    pLoop->pIndex->def->key_def->parts[iEq].sort_order) {
 			testcase(iEq == 0);
 			testcase(bRev);
 			bRev = !bRev;
@@ -736,7 +736,7 @@ codeAllEqualityTerms(Parse * pParse,	/* Parsing context */
 		sqlite3VdbeAddOp1(v, (bRev ? OP_Last : OP_Rewind), iIdxCur);
 		VdbeCoverageIf(v, bRev == 0);
 		VdbeCoverageIf(v, bRev != 0);
-		VdbeComment((v, "begin skip-scan on %s", pIdx->zName));
+		VdbeComment((v, "begin skip-scan on %s", pIdx->def->name));
 		j = sqlite3VdbeAddOp0(v, OP_Goto);
 		pLevel->addrSkip =
 		    sqlite3VdbeAddOp4Int(v, (bRev ? OP_SeekLT : OP_SeekGT),
@@ -746,7 +746,8 @@ codeAllEqualityTerms(Parse * pParse,	/* Parsing context */
 		sqlite3VdbeJumpHere(v, j);
 		for (j = 0; j < nSkip; j++) {
 			sqlite3VdbeAddOp3(v, OP_Column, iIdxCur,
-					  pIdx->aiColumn[j], regBase + j);
+					  pIdx->def->key_def->parts[j].fieldno,
+					  regBase + j);
 			VdbeComment((v, "%s", explainIndexColumnName(pIdx, j)));
 		}
 	}
@@ -1037,14 +1038,14 @@ sqlite3WhereCodeOneLoopStart(WhereInfo * pWInfo,	/* Complete information about t
 		assert(pWInfo->pOrderBy == 0
 		       || pWInfo->pOrderBy->nExpr == 1
 		       || (pWInfo->wctrlFlags & WHERE_ORDERBY_MIN) == 0);
-		int nIdxCol;
+		uint32_t part_count;
 		if (pIdx != NULL)
-			nIdxCol = index_column_count(pIdx);
+			part_count = pIdx->def->key_def->part_count;
 		else
-			nIdxCol = idx_def->key_def->part_count;
-		if ((pWInfo->wctrlFlags & WHERE_ORDERBY_MIN) != 0
-		    && pWInfo->nOBSat > 0 && (nIdxCol > nEq)) {
-			j = pIdx->aiColumn[nEq];
+			part_count = idx_def->key_def->part_count;
+		if ((pWInfo->wctrlFlags & WHERE_ORDERBY_MIN) != 0 &&
+		    pWInfo->nOBSat > 0 && part_count > nEq) {
+			j = pIdx->def->key_def->parts[nEq].fieldno;
 			/* Allow seek for column with `NOT NULL` == false attribute.
 			 * If a column may contain NULL-s, the comparator installed
 			 * by Tarantool is prepared to seek using a NULL value.
@@ -1055,8 +1056,7 @@ sqlite3WhereCodeOneLoopStart(WhereInfo * pWInfo,	/* Complete information about t
 			 * FYI: entries in an index are ordered as follows:
 			 *      NULL, ... NULL, min_value, ...
 			 */
-			if (j >= 0 &&
-			    pIdx->pTable->def->fields[j].is_nullable) {
+			if (pIdx->pTable->def->fields[j].is_nullable) {
 				assert(pLoop->nSkip == 0);
 				bSeekPastNull = 1;
 				nExtraReg = 1;
@@ -1093,16 +1093,16 @@ sqlite3WhereCodeOneLoopStart(WhereInfo * pWInfo,	/* Complete information about t
 				testcase(pIdx->aSortOrder[nEq] ==
 					 SORT_ORDER_DESC);
 				assert((bRev & ~1) == 0);
+				struct key_def *def = pIdx->def->key_def;
 				pLevel->iLikeRepCntr <<= 1;
 				pLevel->iLikeRepCntr |=
-					bRev ^ (sql_index_column_sort_order(pIdx, nEq) ==
+					bRev ^ (def->parts[nEq].sort_order ==
 						SORT_ORDER_DESC);
 			}
 #endif
 			if (pRangeStart == 0) {
-				j = pIdx->aiColumn[nEq];
-				if (j >= 0 &&
-				    pIdx->pTable->def->fields[j].is_nullable)
+				j = pIdx->def->key_def->parts[nEq].fieldno;
+				if (pIdx->pTable->def->fields[j].is_nullable)
 					bSeekPastNull = 1;
 			}
 		}
@@ -1113,10 +1113,9 @@ sqlite3WhereCodeOneLoopStart(WhereInfo * pWInfo,	/* Complete information about t
 		 * a forward order scan on a descending index, interchange the
 		 * start and end terms (pRangeStart and pRangeEnd).
 		 */
-		if ((nEq < nIdxCol &&
-		     bRev == (sql_index_column_sort_order(pIdx, nEq) ==
-			      SORT_ORDER_ASC)) ||
-		    (bRev && nIdxCol == nEq)) {
+		if ((nEq < part_count &&
+		     bRev == (pIdx->def->key_def->parts[nEq].sort_order ==
+			      SORT_ORDER_ASC)) || (bRev && part_count == nEq)) {
 			SWAP(pRangeEnd, pRangeStart);
 			SWAP(bSeekPastNull, bStopAtNull);
 			SWAP(nBtm, nTop);
@@ -1196,16 +1195,16 @@ sqlite3WhereCodeOneLoopStart(WhereInfo * pWInfo,	/* Complete information about t
 			}
 		} else {
 			pk = sqlite3PrimaryKeyIndex(pIdx->pTable);
-			affinity =
-				pIdx->pTable->def->fields[pk->aiColumn[0]].affinity;
+			uint32_t fieldno = pk->def->key_def->parts[0].fieldno;
+			affinity = pIdx->pTable->def->fields[fieldno].affinity;
 		}
 
-		int nPkCol;
+		uint32_t pk_part_count;
 		if (pk != NULL)
-			nPkCol = index_column_count(pk);
+			pk_part_count = pk->def->key_def->part_count;
 		else
-			nPkCol = idx_pk->key_def->part_count;
-		if (nPkCol == 1 && affinity == AFFINITY_INTEGER) {
+			pk_part_count = idx_pk->key_def->part_count;
+		if (pk_part_count == 1 && affinity == AFFINITY_INTEGER) {
 			/* Right now INTEGER PRIMARY KEY is the only option to
 			 * get Tarantool's INTEGER column type. Need special handling
 			 * here: try to loosely convert FLOAT to INT. If RHS type
@@ -1213,8 +1212,9 @@ sqlite3WhereCodeOneLoopStart(WhereInfo * pWInfo,	/* Complete information about t
 			 */
 			int limit = pRangeStart == NULL ? nEq : nEq + 1;
 			for (int i = 0; i < limit; i++) {
-				if ((pIdx != NULL && pIdx->aiColumn[i] ==
-				     pk->aiColumn[0]) ||
+				if ((pIdx != NULL &&
+				     pIdx->def->key_def->parts[i].fieldno ==
+				     pk->def->key_def->parts[0].fieldno) ||
 				    (idx_pk != NULL &&
 				     idx_def->key_def->parts[i].fieldno ==
 				     idx_pk->key_def->parts[0].fieldno)) {
@@ -1326,17 +1326,17 @@ sqlite3WhereCodeOneLoopStart(WhereInfo * pWInfo,	/* Complete information about t
 			/* pIdx is a covering index.  No need to access the main table. */
 		}  else if (iCur != iIdxCur) {
 			Index *pPk = sqlite3PrimaryKeyIndex(pIdx->pTable);
-			int nPkCol = index_column_count(pPk);
-			int iKeyReg = sqlite3GetTempRange(pParse, nPkCol);
-			for (j = 0; j < nPkCol; j++) {
-				k = pPk->aiColumn[j];
+			int pk_part_count = pPk->def->key_def->part_count;
+			int iKeyReg = sqlite3GetTempRange(pParse, pk_part_count);
+			for (j = 0; j < pk_part_count; j++) {
+				k = pPk->def->key_def->parts[j].fieldno;
 				sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, k,
 						  iKeyReg + j);
 			}
 			sqlite3VdbeAddOp4Int(v, OP_NotFound, iCur, addrCont,
-					     iKeyReg, nPkCol);
+					     iKeyReg, pk_part_count);
 			VdbeCoverage(v);
-			sqlite3ReleaseTempRange(pParse, iKeyReg, nPkCol);
+			sqlite3ReleaseTempRange(pParse, iKeyReg, pk_part_count);
 		}
 
 		/* Record the instruction used to terminate the loop. */
@@ -1434,10 +1434,10 @@ sqlite3WhereCodeOneLoopStart(WhereInfo * pWInfo,	/* Complete information about t
 		 */
 		if ((pWInfo->wctrlFlags & WHERE_DUPLICATES_OK) == 0) {
 			Index *pPk = sqlite3PrimaryKeyIndex(pTab);
-			int nPkCol = index_column_count(pPk);
+			int pk_part_count = pPk->def->key_def->part_count;
 			regRowset = pParse->nTab++;
 			sqlite3VdbeAddOp2(v, OP_OpenTEphemeral,
-					  regRowset, nPkCol);
+					  regRowset, pk_part_count);
 			sql_vdbe_set_p4_key_def(pParse, pPk);
 			regPk = ++pParse->nMem;
 		}
@@ -1538,16 +1538,23 @@ sqlite3WhereCodeOneLoopStart(WhereInfo * pWInfo,	/* Complete information about t
 						int iSet =
 						    ((ii == pOrWc->nTerm - 1) ? -1 : ii);
 						Index *pPk = sqlite3PrimaryKeyIndex (pTab);
-						int nPk = index_column_count(pPk);
-						int iPk;
+						struct key_def *def =
+							pPk->def->key_def;
 
 						/* Read the PK into an array of temp registers. */
-						r = sqlite3GetTempRange(pParse, nPk);
-						for (iPk = 0; iPk < nPk; iPk++) {
-							int iCol = pPk->aiColumn[iPk];
+						r = sqlite3GetTempRange(pParse,
+									def->part_count);
+						for (uint32_t iPk = 0;
+						     iPk < def->part_count;
+						     iPk++) {
+							uint32_t fieldno =
+								def->parts[iPk].
+								fieldno;
 							sqlite3ExprCodeGetColumnToReg
-								(pParse, pTab->def,
-								 iCol, iCur,
+								(pParse,
+								 pTab->def,
+								 fieldno,
+								 iCur,
 								 r + iPk);
 						}
 
@@ -1567,20 +1574,21 @@ sqlite3WhereCodeOneLoopStart(WhereInfo * pWInfo,	/* Complete information about t
 							jmp1 = sqlite3VdbeAddOp4Int
 								(v, OP_Found,
 								 regRowset, 0,
-								 r, nPk);
+								 r,
+								 def->part_count);
 							VdbeCoverage(v);
 						}
 						if (iSet >= 0) {
 							sqlite3VdbeAddOp3
 								(v, OP_MakeRecord,
-								 r, nPk, regPk);
+								 r, def->part_count, regPk);
 							sqlite3VdbeAddOp2
 								(v, OP_IdxInsert,
 								 regRowset, regPk);
 						}
 
 						/* Release the array of temp registers */
-						sqlite3ReleaseTempRange(pParse, r, nPk);
+						sqlite3ReleaseTempRange(pParse, r, def->part_count);
 					}
 
 					/* Invoke the main loop body as a subroutine */
diff --git a/test/sql-tap/collation.test.lua b/test/sql-tap/collation1.test.lua
similarity index 100%
rename from test/sql-tap/collation.test.lua
rename to test/sql-tap/collation1.test.lua
diff --git a/test/sql-tap/collation2.test.lua b/test/sql-tap/collation2.test.lua
new file mode 100755
index 000000000..64296b0be
--- /dev/null
+++ b/test/sql-tap/collation2.test.lua
@@ -0,0 +1,20 @@
+#!/usr/bin/env tarantool
+test = require("sqltester")
+test:plan(3)
+
+test:do_catchsql_test(
+        "collation-2.1",
+        'CREATE TABLE test1 (a int, b int, c int, PRIMARY KEY (a, a, a, b, c))',
+        nil)
+
+test:do_catchsql_test(
+        "collation-2.2",
+        'CREATE TABLE test2 (a int, b int, c int, PRIMARY KEY (a, a, a, b, b, a, c))',
+        nil)
+
+test:do_catchsql_test(
+        "collation-2.3",
+        'CREATE TABLE test3 (a int, b int, c int, PRIMARY KEY (a, a COLLATE foo, b, c))',
+        {1, "Collation 'FOO' does not exist"})
+
+test:finish_test()
diff --git a/test/sql-tap/colname.test.lua b/test/sql-tap/colname.test.lua
index c53a1e885..ddc06eea7 100755
--- a/test/sql-tap/colname.test.lua
+++ b/test/sql-tap/colname.test.lua
@@ -643,13 +643,13 @@ test:do_catchsql_test(
     "colname-11.2",
     [[CREATE TABLE t1(a, b, c, d, e, 
       PRIMARY KEY(a), UNIQUE('b' COLLATE "unicode_ci" DESC));]],
-    {1, "/functional indexes aren't supported in the current version/"})
+    {1, "/Tarantool does not support functional indexes/"})
 
 test:execsql("create table table1(a primary key, b, c)")
 
 test:do_catchsql_test(
     "colname-11.3",
     [[ CREATE INDEX t1c ON table1('c'); ]],
-    {1, "/functional indexes aren't supported in the current version/"})
+    {1, "/Tarantool does not support functional indexes/"})
 
 test:finish_test()
diff --git a/test/sql-tap/identifier_case.test.lua b/test/sql-tap/identifier_case.test.lua
index 5e7573ac4..ed9553c6b 100755
--- a/test/sql-tap/identifier_case.test.lua
+++ b/test/sql-tap/identifier_case.test.lua
@@ -206,8 +206,8 @@ data = {
     { 3,  [["binary"]], {0}},
     { 4,  [["bInaRy"]], {0}},
     { 5,  [["unicode"]], {0}},
-    { 6,  [[ unicode ]], {1,"no such collation sequence: UNICODE"}},
-    { 7,  [["UNICODE"]], {1,"no such collation sequence: UNICODE"}}
+    { 6,  [[ unicode ]], {1,"Collation 'UNICODE' does not exist"}},
+    { 7,  [["UNICODE"]], {1,"Collation 'UNICODE' does not exist"}}
 }
 
 test:do_catchsql_test(
diff --git a/test/sql/message-func-indexes.result b/test/sql/message-func-indexes.result
index 4bf1cab49..dbcb12f03 100644
--- a/test/sql/message-func-indexes.result
+++ b/test/sql/message-func-indexes.result
@@ -12,25 +12,25 @@ box.sql.execute("CREATE TABLE t2(object INTEGER PRIMARY KEY, price INTEGER, coun
 -- should return certain message.
 box.sql.execute("CREATE INDEX i1 ON t1(a+1)")
 ---
-- error: functional indexes aren't supported in the current version
+- error: Tarantool does not support functional indexes
 ...
 box.sql.execute("CREATE INDEX i2 ON t1(a)")
 ---
 ...
 box.sql.execute("CREATE INDEX i3 ON t2(price + 100)")
 ---
-- error: functional indexes aren't supported in the current version
+- error: Tarantool does not support functional indexes
 ...
 box.sql.execute("CREATE INDEX i4 ON t2(price)")
 ---
 ...
 box.sql.execute("CREATE INDEX i5 ON t2(count + 1)")
 ---
-- error: functional indexes aren't supported in the current version
+- error: Tarantool does not support functional indexes
 ...
 box.sql.execute("CREATE INDEX i6 ON t2(count * price)")
 ---
-- error: functional indexes aren't supported in the current version
+- error: Tarantool does not support functional indexes
 ...
 -- Cleaning up.
 box.sql.execute("DROP TABLE t1")
--