[tarantool-patches] [PATCH v2] sql: fix decode analyze sample

[AKhatskevich <avkhatskevich@tarantool.org>]

Analyze samples are encoded with msgpack and should be decoded as a
msgpack.

sqlite3Stat4Column sqlite-style function converted to sql_stat4_column
Tarantool-styled.

Closes #2860
---
Changes:
 * sqlite3Stat4Column Tarantool style

Branch: https://github.com/tarantool/tarantool/tree/kh/gh-2860-skip-scan
Issue: https://github.com/tarantool/tarantool/issues/2860

 src/box/sql/sqliteInt.h      | 20 ++++++++++++-
 src/box/sql/vdbemem.c        | 66 +++++++++++++-----------------------------
 src/box/sql/where.c          |  3 +-
 test/sql-tap/whereG.test.lua | 68 +++++++++++++++++++++++++++++++++++++++++++-
 4 files changed, 107 insertions(+), 50 deletions(-)

diff --git a/src/box/sql/sqliteInt.h b/src/box/sql/sqliteInt.h
index 2800be583..b64075959 100644
--- a/src/box/sql/sqliteInt.h
+++ b/src/box/sql/sqliteInt.h
@@ -4020,7 +4020,25 @@ int sqlite3Stat4ProbeSetValue(Parse *, Index *, UnpackedRecord **, Expr *, int,
 			      int, int *);
 int sqlite3Stat4ValueFromExpr(Parse *, Expr *, u8, sqlite3_value **);
 void sqlite3Stat4ProbeFree(UnpackedRecord *);
-int sqlite3Stat4Column(sqlite3 *, const void *, int, int, sqlite3_value **);
+
+/*
+ * Extract the iCol-th column from the record in pRec.  Write
+ * the column value into *ppVal.  If *ppVal is initially NULL
+ * then a new sqlite3_value object is allocated.
+ *
+ * If *ppVal is initially NULL then the caller is responsible for
+ * ensuring that the value written into *ppVal is eventually
+ * freed.
+ *
+ * @param db Database handle.
+ * @param pRec Pointer to buffer containing record.
+ * @param iCol Column to extract.
+ * @param[out] ppVal Extracted value.
+ *
+ * @retval Error code or SQLITE_OK.
+ */
+int
+sql_stat4_column(struct sqlite3 *, const void *, int, sqlite3_value **);
 char sqlite3IndexColumnAffinity(sqlite3 *, Index *, int);
 
 /*
diff --git a/src/box/sql/vdbemem.c b/src/box/sql/vdbemem.c
index f91d7119c..821d4db74 100644
--- a/src/box/sql/vdbemem.c
+++ b/src/box/sql/vdbemem.c
@@ -1588,55 +1588,29 @@ sqlite3Stat4ValueFromExpr(Parse * pParse,	/* Parse context */
 	return stat4ValueFromExpr(pParse, pExpr, affinity, 0, ppVal);
 }
 
-/*
- * Extract the iCol-th column from the nRec-byte record in pRec.  Write
- * the column value into *ppVal.  If *ppVal is initially NULL then a new
- * sqlite3_value object is allocated.
- *
- * If *ppVal is initially NULL then the caller is responsible for
- * ensuring that the value written into *ppVal is eventually freed.
- */
 int
-sqlite3Stat4Column(sqlite3 * db,	/* Database handle */
-		   const void *pRec,	/* Pointer to buffer containing record */
-		   int nRec,	/* Size of buffer pRec in bytes */
-		   int iCol,	/* Column to extract */
-		   sqlite3_value ** ppVal	/* OUT: Extracted value */
-    )
+sql_stat4_column(struct sqlite3 *db, const void *record, int col_num,
+		 sqlite3_value **res)
 {
-	u32 t;			/* a column type code */
-	int nHdr;		/* Size of the header in the record */
-	int iHdr;		/* Next unread header byte */
-	int iField;		/* Next unread data byte */
-	int szField = 0;	/* Size of the current data field */
-	int i;			/* Column index */
-	u8 *a = (u8 *) pRec;	/* Typecast byte array */
-	Mem *pMem = *ppVal;	/* Write result into this Mem object */
-
-	assert(iCol > 0);
-	iHdr = getVarint32(a, nHdr);
-	if (nHdr > nRec || iHdr >= nHdr)
-		return SQLITE_CORRUPT_BKPT;
-	iField = nHdr;
-	for (i = 0; i <= iCol; i++) {
-		iHdr += getVarint32(&a[iHdr], t);
-		testcase(iHdr == nHdr);
-		testcase(iHdr == nHdr + 1);
-		if (iHdr > nHdr)
-			return SQLITE_CORRUPT_BKPT;
-		szField = sqlite3VdbeSerialTypeLen(t);
-		iField += szField;
-	}
-	testcase(iField == nRec);
-	testcase(iField == nRec + 1);
-	if (iField > nRec)
-		return SQLITE_CORRUPT_BKPT;
-	if (pMem == 0) {
-		pMem = *ppVal = sqlite3ValueNew(db);
-		if (pMem == 0)
-			return SQLITE_NOMEM_BKPT;
+	assert(col_num >= 0);
+	/* Write result into this Mem object */
+	Mem *mem = *res;
+	/* Typecast byte array */
+	const char *a = (const char *) record;
+	assert(mp_typeof(a[0]) == MP_ARRAY);
+	int col_cnt = mp_decode_array(&a);
+	assert(col_cnt > col_num);
+	for (int i = 0; i < col_num; i++)
+		mp_next(&a);
+	if (mem == 0) {
+		mem = *res = sqlite3ValueNew(db);
+		if (mem == 0) {
+			diag_set(OutOfMemory, sizeof(Mem), "sqlite3ValeuNew",
+				 "mem");
+			return -1;
+		}
 	}
-	sqlite3VdbeSerialGet(&a[iField - szField], t, pMem);
+	sqlite3VdbeMsgpackGet((const unsigned char *) record, mem);
 	return SQLITE_OK;
 }
 
diff --git a/src/box/sql/where.c b/src/box/sql/where.c
index cde38152a..4a76ed2ec 100644
--- a/src/box/sql/where.c
+++ b/src/box/sql/where.c
@@ -1183,8 +1183,7 @@ whereRangeSkipScanEst(Parse * pParse,		/* Parsing & code generating context */
 		int i;
 		int nDiff;
 		for (i = 0; rc == SQLITE_OK && i < p->nSample; i++) {
-			rc = sqlite3Stat4Column(db, p->aSample[i].p,
-						p->aSample[i].n, nEq, &pVal);
+			rc = sql_stat4_column(db, p->aSample[i].p, nEq, &pVal);
 			if (rc == SQLITE_OK && p1) {
 				int res = sqlite3MemCompare(p1, pVal, pColl);
 				if (res >= 0)
diff --git a/test/sql-tap/whereG.test.lua b/test/sql-tap/whereG.test.lua
index 1842f2ae8..13cef16c8 100755
--- a/test/sql-tap/whereG.test.lua
+++ b/test/sql-tap/whereG.test.lua
@@ -1,6 +1,6 @@
 #!/usr/bin/env tarantool
 test = require("sqltester")
-test:plan(20)
+test:plan(23)
 
 --!./tcltestrunner.lua
 -- 2013-09-05
@@ -388,5 +388,71 @@ test:do_execsql_test(
         -- </7.3>
     })
 
+-- gh-2860 skip-scan plan
+test:execsql([[
+    CREATE TABLE people(name TEXT PRIMARY KEY, role TEXT NOT NULL,
+        height INT NOT NULL, CHECK(role IN ('student','teacher')));
+    CREATE INDEX people_idx1 ON people(role, height);
+    INSERT INTO people VALUES('Alice','student',156);
+    INSERT INTO people VALUES('Bob','student',161);
+    INSERT INTO people VALUES('Cindy','student',155);
+    INSERT INTO people VALUES('David','student',181);
+    INSERT INTO people VALUES('Emily','teacher',158);
+    INSERT INTO people VALUES('Fred','student',163);
+    INSERT INTO people VALUES('Ginny','student',169);
+    INSERT INTO people VALUES('Harold','student',172);
+    INSERT INTO people VALUES('Imma','student',179);
+    INSERT INTO people VALUES('Jack','student',181);
+    INSERT INTO people VALUES('Karen','student',163);
+    INSERT INTO people VALUES('Logan','student',177);
+    INSERT INTO people VALUES('Megan','teacher',159);
+    INSERT INTO people VALUES('Nathan','student',163);
+    INSERT INTO people VALUES('Olivia','student',161);
+    INSERT INTO people VALUES('Patrick','teacher',180);
+    INSERT INTO people VALUES('Quiana','student',182);
+    INSERT INTO people VALUES('Robert','student',159);
+    INSERT INTO people VALUES('Sally','student',166);
+    INSERT INTO people VALUES('Tom','student',171);
+    INSERT INTO people VALUES('Ursula','student',170);
+    INSERT INTO people VALUES('Vance','student',179);
+    INSERT INTO people VALUES('Willma','student',175);
+    INSERT INTO people VALUES('Xavier','teacher',185);
+    INSERT INTO people VALUES('Yvonne','student',149);
+    INSERT INTO people VALUES('Zach','student',170);
+    INSERT INTO people VALUES('Angie','student',166);
+    INSERT INTO people VALUES('Brad','student',176);
+    INSERT INTO people VALUES('Claire','student',168);
+    INSERT INTO people VALUES('Donald','student',162);
+    INSERT INTO people VALUES('Elaine','student',177);
+    INSERT INTO people VALUES('Frazier','student',159);
+    INSERT INTO people VALUES('Grace','student',179);
+    INSERT INTO people VALUES('Horace','student',166);
+    INSERT INTO people VALUES('Ingrad','student',155);
+    INSERT INTO people VALUES('Jacob','student',179);
+    INSERT INTO people VALUES('John', 'student', 154);
+]])
+
+test:do_execsql_test(
+    "7.1",
+    [[
+        SELECT name FROM people WHERE height>=180 order by name;
+    ]],
+    {"David","Jack","Patrick","Quiana","Xavier"})
+
+test:do_execsql_test(
+    "7.2",
+    [[
+        EXPLAIN QUERY PLAN SELECT name FROM people WHERE height>=180;
+    ]],
+    {0,0,0,"SCAN TABLE PEOPLE"})
+
+test:do_execsql_test(
+    "7.3",
+    [[
+        ANALYZE;
+        EXPLAIN QUERY PLAN SELECT name FROM people WHERE height>=180;
+    ]],
+    {0,0,0,"SEARCH TABLE PEOPLE USING COVERING INDEX PEOPLE_IDX1" ..
+        " (ANY(ROLE) AND HEIGHT>?)"})
 
 test:finish_test()
-- 
2.14.1