[tarantool-patches] Re: [PATCH v1 1/2] sql: restrict nullable action definitions

[Kirill Shcherbatov <kshcherbatov@tarantool.org>]

> I have pushed my review fixes on the branch, and they
> correct some of the comments. Please, finish the patch
> after my fixes including rest of the comments.
Thank you for review, I've fixed all problems on branch and squashed.

> 1. Please, remove is_primkey. It is not needed here and can be easily
> removed together with merging this cycle into the code below. The
> only place where it is still used except here is
> check_on_conflict_replace_entries, that can be spread over other
> primary key checks.
> 2. Please, use ER_NULLABLE_PRIMARY.
> 3. This is checked already, so the rest of hunk below can be removed.
Fixed with review fixes.

> 4. This test does not work, it fails on syntax, but must fail on action.
Ok, I've hacked to make it work this way.


============================================


This patch dissallows define multiple "NULL", "NOT NULL"
options per column and fixes silent implicit behavior
for invalid "NULL PRIMARY KEY" construction.

Closes #3473.
---
 src/box/sql/build.c           | 86 +++++++++++++++++++++++++++++++++----------
 src/box/sql/parse.y           |  7 +++-
 test/sql/on-conflict.result   | 21 +++++++++++
 test/sql/on-conflict.test.lua |  8 ++++
 4 files changed, 101 insertions(+), 21 deletions(-)

diff --git a/src/box/sql/build.c b/src/box/sql/build.c
index 8fba373..925193e 100644
--- a/src/box/sql/build.c
+++ b/src/box/sql/build.c
@@ -653,7 +653,12 @@ sqlite3AddColumn(Parse * pParse, Token * pName, Token * pType)
 	struct field_def *column_def = &p->def->fields[p->def->field_count];
 	memcpy(column_def, &field_def_default, sizeof(field_def_default));
 	column_def->name = z;
-	column_def->nullable_action = ON_CONFLICT_ACTION_NONE;
+	/*
+	 * Marker on_conflict_action_MAX is used to detect
+	 * attempts to define NULL multiple time or to detect
+	 * invalid primary key definition.
+	 */
+	column_def->nullable_action = on_conflict_action_MAX;
 	column_def->is_nullable = true;
 
 	if (pType->n == 0) {
@@ -701,9 +706,22 @@ sqlite3AddNotNull(Parse * pParse, int onError)
 	p = pParse->pNewTable;
 	if (p == 0 || NEVER(p->def->field_count < 1))
 		return;
-	p->def->fields[p->def->field_count - 1].nullable_action = (u8)onError;
-	p->def->fields[p->def->field_count - 1].is_nullable =
-		action_is_nullable(onError);
+	struct field_def *field = &p->def->fields[p->def->field_count - 1];
+	if (field->nullable_action != on_conflict_action_MAX) {
+		/* Prevent defining nullable_action many times. */
+		const char *err_msg =
+			tt_sprintf("NULL declaration for column '%s' of table "
+				   "'%s' has been already set to '%s'",
+				   field->name, p->def->name,
+				   on_conflict_action_strs[field->
+							   nullable_action]);
+		diag_set(ClientError, ER_SQL, err_msg);
+		pParse->rc = SQL_TARANTOOL_ERROR;
+		pParse->nErr++;
+		return;
+	}
+	field->nullable_action = onError;
+	field->is_nullable = action_is_nullable(onError);
 }
 
 /*
@@ -1283,6 +1301,24 @@ hasColumn(const i16 * aiCol, int nCol, int x)
 	return 0;
 }
 
+static int
+field_def_create_for_pk(struct Parse *parser, struct field_def *field,
+			const char *space_name)
+{
+	if (field->nullable_action != ON_CONFLICT_ACTION_ABORT &&
+	    field->nullable_action != ON_CONFLICT_ACTION_DEFAULT &&
+	    field->nullable_action != on_conflict_action_MAX) {
+		diag_set(ClientError, ER_NULLABLE_PRIMARY, space_name);
+		parser->rc = SQL_TARANTOOL_ERROR;
+		parser->nErr++;
+		return -1;
+	} else if (field->nullable_action == on_conflict_action_MAX) {
+		field->nullable_action = ON_CONFLICT_ACTION_ABORT;
+		field->is_nullable = false;
+	}
+	return 0;
+}
+
 /*
  * This routine runs at the end of parsing a CREATE TABLE statement.
  * The job of this routine is to convert both
@@ -1301,18 +1337,8 @@ 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++) {
-			if (pTab->aCol[i].is_primkey) {
-				pTab->def->fields[i].nullable_action
-					= ON_CONFLICT_ACTION_ABORT;
-				pTab->def->fields[i].is_nullable = false;
-			}
-		}
-	}
+	struct field_def *fields = pTab->def->fields;
+	const char *space_name = pTab->def->name;
 
 	/* Locate the PRIMARY KEY index.  Or, if this table was originally
 	 * an INTEGER PRIMARY KEY table, create a new PRIMARY KEY index.
@@ -1320,7 +1346,10 @@ convertToWithoutRowidTable(Parse * pParse, Table * pTab)
 	if (pTab->iPKey >= 0) {
 		ExprList *pList;
 		Token ipkToken;
-		sqlite3TokenInit(&ipkToken, pTab->def->fields[pTab->iPKey].name);
+		struct field_def *field = &fields[pTab->iPKey];
+		if (field_def_create_for_pk(pParse, field, space_name) != 0)
+			return;
+		sqlite3TokenInit(&ipkToken, field->name);
 		pList = sql_expr_list_append(pParse->db, NULL,
 					     sqlite3ExprAlloc(db, TK_ID,
 							      &ipkToken, 0));
@@ -1343,11 +1372,17 @@ convertToWithoutRowidTable(Parse * pParse, Table * pTab)
 		 * "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])) {
+		u16 pk_columns = pPk->nColumn;
+		for (i = j = 0; i < pk_columns; i++) {
+			uint32_t part_no = pPk->aiColumn[i];
+			if (hasColumn(pPk->aiColumn, j, part_no)) {
 				pPk->nColumn--;
 			} else {
-				pPk->aiColumn[j++] = pPk->aiColumn[i];
+				pPk->aiColumn[j++] = part_no;
+				if (field_def_create_for_pk(pParse,
+							    &fields[part_no],
+							    space_name) != 0)
+					return;
 			}
 		}
 		pPk->nColumn = j;
@@ -1736,6 +1771,17 @@ sqlite3EndTable(Parse * pParse,	/* Parse context */
 			return;
 		} else {
 			convertToWithoutRowidTable(pParse, p);
+			if (pParse->nErr > 0)
+				return;
+		}
+	}
+
+	/* Set default on_nullable action if required. */
+	struct field_def *field = p->def->fields;
+	for (uint32_t i = 0; i < p->def->field_count; ++i, ++field) {
+		if (field->nullable_action == on_conflict_action_MAX) {
+			field->nullable_action = ON_CONFLICT_ACTION_NONE;
+			field->is_nullable = true;
 		}
 	}
 
diff --git a/src/box/sql/parse.y b/src/box/sql/parse.y
index ac935fd..e2bdc4a 100644
--- a/src/box/sql/parse.y
+++ b/src/box/sql/parse.y
@@ -276,7 +276,12 @@ ccons ::= DEFAULT id(X).              {
 // In addition to the type name, we also care about the primary key and
 // UNIQUE constraints.
 //
-ccons ::= NULL onconf.
+ccons ::= NULL onconf(R).        {
+    sqlite3AddNotNull(pParse, ON_CONFLICT_ACTION_NONE);
+    /* Trigger nullability mismatch error if required. */
+    if (R != ON_CONFLICT_ACTION_DEFAULT)
+        sqlite3AddNotNull(pParse, R);
+}
 ccons ::= NOT NULL onconf(R).    {sqlite3AddNotNull(pParse, R);}
 ccons ::= PRIMARY KEY sortorder(Z) onconf(R) autoinc(I).
                                  {sqlite3AddPrimaryKey(pParse,0,R,I,Z);}
diff --git a/test/sql/on-conflict.result b/test/sql/on-conflict.result
index c0d0de0..2970cb8 100644
--- a/test/sql/on-conflict.result
+++ b/test/sql/on-conflict.result
@@ -99,3 +99,24 @@ box.sql.execute('DROP TABLE t1')
 box.sql.execute('DROP TABLE t2')
 ---
 ...
+--
+-- gh-3473: Primary key can be declared with NULL.
+--
+box.sql.execute('CREATE TABLE te17 (s1 INT NULL PRIMARY KEY NOT NULL);')
+---
+- error: 'SQL error: NULL declaration for column ''S1'' of table ''TE17'' has been
+    already set to ''none'''
+...
+box.sql.execute('CREATE TABLE te17 (s1 INT NULL PRIMARY KEY);')
+---
+- error: Primary index of the space 'TE17' can not contain nullable parts
+...
+box.sql.execute("CREATE TABLE test (a int PRIMARY KEY, b int NULL ON CONFLICT IGNORE);")
+---
+- error: 'SQL error: NULL declaration for column ''B'' of table ''TEST'' has been
+    already set to ''none'''
+...
+box.sql.execute("CREATE TABLE test (a int, b int NULL, c int, PRIMARY KEY(a, b, c))")
+---
+- error: Primary index of the space 'TEST' can not contain nullable parts
+...
diff --git a/test/sql/on-conflict.test.lua b/test/sql/on-conflict.test.lua
index b6d92f7..5ae6b0c 100644
--- a/test/sql/on-conflict.test.lua
+++ b/test/sql/on-conflict.test.lua
@@ -38,3 +38,11 @@ box.sql.execute('DROP TABLE p')
 box.sql.execute('DROP TABLE e')
 box.sql.execute('DROP TABLE t1')
 box.sql.execute('DROP TABLE t2')
+
+--
+-- gh-3473: Primary key can be declared with NULL.
+--
+box.sql.execute('CREATE TABLE te17 (s1 INT NULL PRIMARY KEY NOT NULL);')
+box.sql.execute('CREATE TABLE te17 (s1 INT NULL PRIMARY KEY);')
+box.sql.execute("CREATE TABLE test (a int PRIMARY KEY, b int NULL ON CONFLICT IGNORE);")
+box.sql.execute("CREATE TABLE test (a int, b int NULL, c int, PRIMARY KEY(a, b, c))")
-- 
2.7.4