Remove unused variable from struct WhereInfo. Add some explanatory comments to new code.

FossilOrigin-Name: f5313e0c680d9baebefb1cf50ddadedd4418a334

manifest

@@ -1,5 +1,5 @@
-C Minor\sperformance\senhancements\sto\sSQLITE_ENABLE_STMT_SCANSTATUS\scode.
-D 2014-11-01T21:00:04.841
+C Remove\sunused\svariable\sfrom\sstruct\sWhereInfo.\sAdd\ssome\sexplanatory\scomments\sto\snew\scode.
+D 2014-11-03T11:25:32.305
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in cf57f673d77606ab0f2d9627ca52a9ba1464146a
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -290,10 +290,10 @@ F src/utf.c fc6b889ba0779b7722634cdeaa25f1930d93820c
 F src/util.c 3b627daa45c7308c1e36e3dbaa3f9ce7e5c7fa73
 F src/vacuum.c 59f03f92bcff57faa6a8ca256eb29ccddfb0614a
 F src/vdbe.c ccc626d70659160596d28b4a910b6086da788695
-F src/vdbe.h 7d603b93d128e614ba2600f12a6c541435405522
-F src/vdbeInt.h 21570e5ec8b3a385d003e6e20f3a91712b7050e5
-F src/vdbeapi.c 19e433e69fe2b27bfc9337a207b6ebf499f41d03
-F src/vdbeaux.c 2887d02721c540b25969d3260d0d3d5668d11583
+F src/vdbe.h d412bd01e89f0d69991b8f46601f96bc169d28f4
+F src/vdbeInt.h 539ba284790e871f98be74a78cbdfcedfae22639
+F src/vdbeapi.c addf446ecade237bebd7e9fe769bdfb9db8d9fb1
+F src/vdbeaux.c 0aeb90cb62d7c07572798b41882838b3d4e55b44
 F src/vdbeblob.c 8b5442ff0954c44b45cbabbe2e94091a2e16fdef
 F src/vdbemem.c 31d8eabb0cd78bfeab4e5124c7363c3e9e54db9f
 F src/vdbesort.c 975aeffa99acb0991b2f288d30294756bff41438
@@ -302,8 +302,8 @@ F src/vtab.c 2a30791bbd7926b589401bd09c3abb33de563793
 F src/wal.c 10e7de7ce90865a68153f001a61f1d985cd17983
 F src/wal.h df01efe09c5cb8c8e391ff1715cca294f89668a4
 F src/walker.c c253b95b4ee44b21c406e2a1052636c31ea27804
-F src/where.c ad4a3bca9070e013ff41e8e63835788bcc43dd1c
-F src/whereInt.h a2bc22f4e3e70eeaa57272f354c288bc3b71b80b
+F src/where.c 53dae5ed6133438a9342c17bf3e95e00edbb0556
+F src/whereInt.h d3633e9b592103241b74b0ec76185f3e5b8b62e0
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/aggerror.test a867e273ef9e3d7919f03ef4f0e8c0d2767944f2
 F test/aggnested.test b35b4cd69fc913f90d39a575e171e1116c3a4bb7
@@ -801,7 +801,7 @@ F test/savepoint4.test c8f8159ade6d2acd9128be61e1230f1c1edc6cc0
 F test/savepoint5.test 0735db177e0ebbaedc39812c8d065075d563c4fd
 F test/savepoint6.test f41279c5e137139fa5c21485773332c7adb98cd7
 F test/savepoint7.test fbf319a7b2dda089ec5be30a424a0e95f121d423
-F test/scanstatus.test 40c7712c8bc0adc3fb88e0419356880679a3a5fb
+F test/scanstatus.test 0c0baa647e98940d753d40691bf6475345c05cc5
 F test/schema.test 8f7999be894260f151adf15c2c7540f1c6d6a481
 F test/schema2.test 906408621ea881fdb496d878b1822572a34e32c5
 F test/schema3.test 1bc1008e1f8cb5654b248c55f27249366eb7ed38
@@ -1211,7 +1211,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 0abfd78ceb09b7f7c27c688c8e3fe93268a13b32
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 9ea37422a8cc2fce51bb10508e5e90f40fd4b511
-R 4191876729196c1564c4c28cce5855c1
+P f13d6ba8a72d75838c4aaf85326c1129da027f8b
+R 79a96158570090f7f8b0799c9e59db67
 U dan
-Z 150c277a759b1b656399ef38dfe29c92
+Z b85dee7fa48b3d6596e077d675db2dc9

manifest.uuid

@@ -1 +1 @@
-f13d6ba8a72d75838c4aaf85326c1129da027f8b
+f5313e0c680d9baebefb1cf50ddadedd4418a334

src/vdbe.h

@@ -283,9 +283,9 @@ void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
 #endif
 
 #ifdef SQLITE_ENABLE_STMT_SCANSTATUS
-void sqlite3VdbeScanCounter(Vdbe*, int, int, int, i64, const char*);
+void sqlite3VdbeScanStatus(Vdbe*, int, int, int, i64, const char*);
 #else
-# define sqlite3VdbeScanCounter(a,b,c,d,e)
+# define sqlite3VdbeScanStatus(a,b,c,d,e)
 #endif
 
 #endif

src/vdbeInt.h

@@ -297,8 +297,8 @@ struct Explain {
 */
 typedef unsigned bft;  /* Bit Field Type */
 
-typedef struct ScanCounter ScanCounter;
-struct ScanCounter {
+typedef struct ScanStatus ScanStatus;
+struct ScanStatus {
   int addrExplain;                /* OP_Explain for loop */
   int addrLoop;                   /* Address of "loops" counter */
   int addrVisit;                  /* Address of "rows visited" counter */
@@ -381,7 +381,7 @@ struct Vdbe {
 #ifdef SQLITE_ENABLE_STMT_SCANSTATUS
   i64 *anExec;            /* Number of times each op has been executed */
   int nScan;              /* Entries in aScan[] */
-  ScanCounter *aScan;     /* Scan definitions for sqlite3_stmt_scanstatus() */
+  ScanStatus *aScan;      /* Scan definitions for sqlite3_stmt_scanstatus() */
 #endif
 };
 

src/vdbeapi.c

@@ -1490,7 +1490,7 @@ int sqlite3_stmt_scanstatus(
   const char **pzExplain          /* OUT: EQP string */
 ){
   Vdbe *p = (Vdbe*)pStmt;
-  ScanCounter *pScan;
+  ScanStatus *pScan;
   if( idx<0 || idx>=p->nScan ) return 1;
   pScan = &p->aScan[idx];
   if( pnLoop ) *pnLoop = p->anExec[pScan->addrLoop];

src/vdbeaux.c

@@ -601,7 +601,7 @@ int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp, int iLineno){
 /*
 ** Add an entry to the array of counters managed by sqlite3_stmt_scanstatus().
 */
-void sqlite3VdbeScanCounter(
+void sqlite3VdbeScanStatus(
   Vdbe *p,                        /* VM to add scanstatus() to */
   int addrExplain,                /* Address of OP_Explain (or 0) */
   int addrLoop,                   /* Address of loop counter */ 
@@ -609,11 +609,11 @@ void sqlite3VdbeScanCounter(
   i64 nEst,                       /* Estimated number of rows */
   const char *zName               /* Name of table or index being scanned */
 ){
-  int nByte = (p->nScan+1) * sizeof(ScanCounter);
-  ScanCounter *aNew;
-  aNew = (ScanCounter*)sqlite3DbRealloc(p->db, p->aScan, nByte);
+  int nByte = (p->nScan+1) * sizeof(ScanStatus);
+  ScanStatus *aNew;
+  aNew = (ScanStatus*)sqlite3DbRealloc(p->db, p->aScan, nByte);
   if( aNew ){
-    ScanCounter *pNew = &aNew[p->nScan++];
+    ScanStatus *pNew = &aNew[p->nScan++];
     pNew->addrExplain = addrExplain;
     pNew->addrLoop = addrLoop;
     pNew->addrVisit = addrVisit;

src/where.c

@@ -2808,9 +2808,12 @@ static void explainIndexRange(StrAccum *pStr, WhereLoop *pLoop, Table *pTab){
 
 /*
 ** This function is a no-op unless currently processing an EXPLAIN QUERY PLAN
-** command. If the query being compiled is an EXPLAIN QUERY PLAN, a single
-** record is added to the output to describe the table scan strategy in 
-** pLevel.
+** command, or if either SQLITE_DEBUG or SQLITE_ENABLE_STMT_SCANSTATUS was
+** defined at compile-time. If it is not a no-op, a single OP_Explain opcode 
+** is added to the output to describe the table scan strategy in pLevel.
+**
+** If an OP_Explain opcode is added to the VM, its address is returned.
+** Otherwise, if no OP_Explain is coded, zero is returned.
 */
 static int explainOneScan(
   Parse *pParse,                  /* Parse context */
@@ -2919,11 +2922,20 @@ static int explainOneScan(
 #endif /* SQLITE_OMIT_EXPLAIN */
 
 #ifdef SQLITE_ENABLE_STMT_SCANSTATUS
+/*
+** Configure the VM passed as the first argument with an
+** sqlite3_stmt_scanstatus() entry corresponding to the scan used to 
+** implement level pLvl. Argument pSrclist is a pointer to the FROM 
+** clause that the scan reads data from.
+**
+** If argument addrExplain is not 0, it must be the address of an 
+** OP_Explain instruction that describes the same loop.
+*/
 static void addScanStatus(
-  Vdbe *v, 
-  SrcList *pSrclist,
-  WhereLevel *pLvl,
-  int addrExplain
+  Vdbe *v,                        /* Vdbe to add scanstatus entry to */
+  SrcList *pSrclist,              /* FROM clause pLvl reads data from */
+  WhereLevel *pLvl,               /* Level to add scanstatus() entry for */
+  int addrExplain                 /* Address of OP_Explain (or 0) */
 ){
   const char *zObj = 0;
   i64 nEst = 1;
@@ -2936,7 +2948,7 @@ static void addScanStatus(
   if( pLoop->nOut>=10 ){
     nEst = sqlite3LogEstToInt(pLoop->nOut);
   }
-  sqlite3VdbeScanCounter(
+  sqlite3VdbeScanStatus(
       v, addrExplain, pLvl->addrBody, pLvl->addrVisit, nEst, zObj
   );
 }

src/whereInt.h

@@ -410,7 +410,6 @@ struct WhereInfo {
   int iTop;                 /* The very beginning of the WHERE loop */
   int iContinue;            /* Jump here to continue with next record */
   int iBreak;               /* Jump here to break out of the loop */
-  int iExplain;             /* Address of OP_Explain (if WHERE_ONETABLE_ONLY) */
   int savedNQueryLoop;      /* pParse->nQueryLoop outside the WHERE loop */
   int aiCurOnePass[2];      /* OP_OpenWrite cursors for the ONEPASS opt */
   WhereMaskSet sMaskSet;    /* Map cursor numbers to bitmasks */

test/scanstatus.test

@@ -231,4 +231,39 @@ do_scanstatus_test 3.4.2 {
   zExplain {SEARCH TABLE a1 USING INTEGER PRIMARY KEY (rowid=?)}
 }
 
+#-------------------------------------------------------------------------
+# Test that scanstatus() data is not available for searches performed
+# by triggers.
+#
+# It is available for searches performed as part of FK processing, but 
+# not FK action processing.
+#
+do_execsql_test 4.0 {
+  CREATE TABLE t1(a, b, c);
+  CREATE TABLE t2(x PRIMARY KEY, y, z);
+  CREATE TRIGGER tr1 AFTER INSERT ON t1 BEGIN
+    SELECT * FROM t2 WHERE x BETWEEN 20 AND 40;
+  END;
+  WITH d(x) AS (SELECT 1 UNION ALL SELECT x+1 AS n FROM d WHERE n<=100)
+  INSERT INTO t2 SELECT x, x*2, x*3 FROM d;
+}
+
+do_execsql_test    4.1.1 { INSERT INTO t1 VALUES(1, 2, 3); }
+do_scanstatus_test 4.1.2 { }
+
+do_execsql_test 4.2 {
+  CREATE TABLE p1(x PRIMARY KEY);
+  INSERT INTO p1 VALUES(1), (2), (3), (4);
+  CREATE TABLE c1(y REFERENCES p1);
+  INSERT INTO c1 VALUES(1), (2), (3);
+  PRAGMA foreign_keys=on;
+}
+do_execsql_test    4.2.1 { DELETE FROM p1 WHERE x=4 }
+do_scanstatus_test 4.2.2 { 
+  nLoop 1 nVisit 1 nEst 1 zName sqlite_autoindex_p1_1 
+  zExplain {SEARCH TABLE p1 USING INDEX sqlite_autoindex_p1_1 (x=?)}
+
+  nLoop 1 nVisit 3 nEst 524288 zName c1 zExplain {SCAN TABLE c1}
+}
+
 finish_test