/ Check-in [b29e02f8]
Login
SQLite training in Houston TX on 2019-11-05 (details)
Part of the 2019 Tcl Conference

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Add the OP_ColumnsUsed opcode (when compiled with SQLITE_ENABLE_COLUMN_USED_MASK) as a hint to the b-tree layer as to which columns of a btree cursor will be used. (Backport from 3.8.11)
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | branch-3.8.9
Files: files | file ages | folders
SHA3-256: b29e02f877d7b85f783a9255794883a85590ff8eafac130a3234eb65d0f717f1
User & Date: drh 2018-12-14 20:20:37
Context
2018-12-14
20:28
Add a missing OP_ColumnsUsed opcode to code for expressions like "? IN (SELECT ...)" in cases where expression can use an index that may contain NULL values. (Backported fix from version 3.14.0). Leaf check-in: 11368e67 user: drh tags: branch-3.8.9
20:20
Add the OP_ColumnsUsed opcode (when compiled with SQLITE_ENABLE_COLUMN_USED_MASK) as a hint to the b-tree layer as to which columns of a btree cursor will be used. (Backport from 3.8.11) check-in: b29e02f8 user: drh tags: branch-3.8.9
2017-11-14
18:26
Fix the SQLITE_ENABLE_UPDATE_DELETE_LIMIT functionality so that it works with views and WITHOUT ROWID tables. This is a modified cherrypick of [dae4a97a]. check-in: b2679d3b user: dan tags: branch-3.8.9
2015-06-12
12:54
Add the OP_ColumnsUsed opcode (when compiled with SQLITE_ENABLE_COLUMN_USED_MASK) as a hint to the b-tree layer as to which columns of a btree cursor will be used. check-in: 711a176c user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/expr.c.

2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
....
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
  }
  sqlite3ReleaseTempReg(pParse, r1);
  sqlite3ExprCachePop(pParse);
  VdbeComment((v, "end IN expr"));
}
#endif /* SQLITE_OMIT_SUBQUERY */

/*
** Duplicate an 8-byte value
*/
static char *dup8bytes(Vdbe *v, const char *in){
  char *out = sqlite3DbMallocRaw(sqlite3VdbeDb(v), 8);
  if( out ){
    memcpy(out, in, 8);
  }
  return out;
}

#ifndef SQLITE_OMIT_FLOATING_POINT
/*
** Generate an instruction that will put the floating point
** value described by z[0..n-1] into register iMem.
**
** The z[] string will probably not be zero-terminated.  But the 
** z[n] character is guaranteed to be something that does not look
** like the continuation of the number.
*/
static void codeReal(Vdbe *v, const char *z, int negateFlag, int iMem){
  if( ALWAYS(z!=0) ){
    double value;
    char *zV;
    sqlite3AtoF(z, &value, sqlite3Strlen30(z), SQLITE_UTF8);
    assert( !sqlite3IsNaN(value) ); /* The new AtoF never returns NaN */
    if( negateFlag ) value = -value;
    zV = dup8bytes(v, (char*)&value);
    sqlite3VdbeAddOp4(v, OP_Real, 0, iMem, 0, zV, P4_REAL);
  }
}
#endif


/*
** Generate an instruction that will put the integer describe by
................................................................................
  }else{
    int c;
    i64 value;
    const char *z = pExpr->u.zToken;
    assert( z!=0 );
    c = sqlite3DecOrHexToI64(z, &value);
    if( c==0 || (c==2 && negFlag) ){
      char *zV;
      if( negFlag ){ value = c==2 ? SMALLEST_INT64 : -value; }
      zV = dup8bytes(v, (char*)&value);
      sqlite3VdbeAddOp4(v, OP_Int64, 0, iMem, 0, zV, P4_INT64);
    }else{
#ifdef SQLITE_OMIT_FLOATING_POINT
      sqlite3ErrorMsg(pParse, "oversized integer: %s%s", negFlag ? "-" : "", z);
#else
#ifndef SQLITE_OMIT_HEX_INTEGER
      if( sqlite3_strnicmp(z,"0x",2)==0 ){
        sqlite3ErrorMsg(pParse, "hex literal too big: %s", z);







<
<
<
<
<
<
<
<
<
<
<












<



<
|







 







<

<
|







2202
2203
2204
2205
2206
2207
2208











2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220

2221
2222
2223

2224
2225
2226
2227
2228
2229
2230
2231
....
2243
2244
2245
2246
2247
2248
2249

2250

2251
2252
2253
2254
2255
2256
2257
2258
  }
  sqlite3ReleaseTempReg(pParse, r1);
  sqlite3ExprCachePop(pParse);
  VdbeComment((v, "end IN expr"));
}
#endif /* SQLITE_OMIT_SUBQUERY */












#ifndef SQLITE_OMIT_FLOATING_POINT
/*
** Generate an instruction that will put the floating point
** value described by z[0..n-1] into register iMem.
**
** The z[] string will probably not be zero-terminated.  But the 
** z[n] character is guaranteed to be something that does not look
** like the continuation of the number.
*/
static void codeReal(Vdbe *v, const char *z, int negateFlag, int iMem){
  if( ALWAYS(z!=0) ){
    double value;

    sqlite3AtoF(z, &value, sqlite3Strlen30(z), SQLITE_UTF8);
    assert( !sqlite3IsNaN(value) ); /* The new AtoF never returns NaN */
    if( negateFlag ) value = -value;

    sqlite3VdbeAddOp4Dup8(v, OP_Real, 0, iMem, 0, (u8*)&value, P4_REAL);
  }
}
#endif


/*
** Generate an instruction that will put the integer describe by
................................................................................
  }else{
    int c;
    i64 value;
    const char *z = pExpr->u.zToken;
    assert( z!=0 );
    c = sqlite3DecOrHexToI64(z, &value);
    if( c==0 || (c==2 && negFlag) ){

      if( negFlag ){ value = c==2 ? SMALLEST_INT64 : -value; }

      sqlite3VdbeAddOp4Dup8(v, OP_Int64, 0, iMem, 0, (u8*)&value, P4_INT64);
    }else{
#ifdef SQLITE_OMIT_FLOATING_POINT
      sqlite3ErrorMsg(pParse, "oversized integer: %s%s", negFlag ? "-" : "", z);
#else
#ifndef SQLITE_OMIT_HEX_INTEGER
      if( sqlite3_strnicmp(z,"0x",2)==0 ){
        sqlite3ErrorMsg(pParse, "hex literal too big: %s", z);

Changes to src/vdbe.c.

3499
3500
3501
3502
3503
3504
3505




















3506
3507
3508
3509
3510
3511
3512
*/
case OP_Close: {
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  sqlite3VdbeFreeCursor(p, p->apCsr[pOp->p1]);
  p->apCsr[pOp->p1] = 0;
  break;
}





















/* Opcode: SeekGE P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
** use the value in register P3 as the key.  If cursor P1 refers 
** to an SQL index, then P3 is the first in an array of P4 registers 







>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
*/
case OP_Close: {
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  sqlite3VdbeFreeCursor(p, p->apCsr[pOp->p1]);
  p->apCsr[pOp->p1] = 0;
  break;
}

#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
/* Opcode: ColumnsUsed P1 * * P4 *
**
** This opcode (which only exists if SQLite was compiled with
** SQLITE_ENABLE_COLUMN_USED_MASK) identifies which columns of the
** table or index for cursor P1 are used.  P4 is a 64-bit integer
** (P4_INT64) in which the first 63 bits are one for each of the
** first 63 columns of the table or index that are actually used
** by the cursor.  The high-order bit is set if any column after
** the 64th is used.
*/
case OP_ColumnsUsed: {
  VdbeCursor *pC;
  pC = p->apCsr[pOp->p1];
  assert( pC->pCursor );
  pC->maskUsed = *(u64*)pOp->p4.pI64;
  break;
}
#endif

/* Opcode: SeekGE P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys), 
** use the value in register P3 as the key.  If cursor P1 refers 
** to an SQL index, then P3 is the first in an array of P4 registers 

Changes to src/vdbe.h.

165
166
167
168
169
170
171

172
173
174
175
176
177
178
*/
Vdbe *sqlite3VdbeCreate(Parse*);
int sqlite3VdbeAddOp0(Vdbe*,int);
int sqlite3VdbeAddOp1(Vdbe*,int,int);
int sqlite3VdbeAddOp2(Vdbe*,int,int,int);
int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int);
int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int);

int sqlite3VdbeAddOp4Int(Vdbe*,int,int,int,int,int);
int sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp, int iLineno);
void sqlite3VdbeAddParseSchemaOp(Vdbe*,int,char*);
void sqlite3VdbeChangeP1(Vdbe*, u32 addr, int P1);
void sqlite3VdbeChangeP2(Vdbe*, u32 addr, int P2);
void sqlite3VdbeChangeP3(Vdbe*, u32 addr, int P3);
void sqlite3VdbeChangeP5(Vdbe*, u8 P5);







>







165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
*/
Vdbe *sqlite3VdbeCreate(Parse*);
int sqlite3VdbeAddOp0(Vdbe*,int);
int sqlite3VdbeAddOp1(Vdbe*,int,int);
int sqlite3VdbeAddOp2(Vdbe*,int,int,int);
int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int);
int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int);
int sqlite3VdbeAddOp4Dup8(Vdbe*,int,int,int,int,const u8*,int);
int sqlite3VdbeAddOp4Int(Vdbe*,int,int,int,int,int);
int sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp, int iLineno);
void sqlite3VdbeAddParseSchemaOp(Vdbe*,int,char*);
void sqlite3VdbeChangeP1(Vdbe*, u32 addr, int P1);
void sqlite3VdbeChangeP2(Vdbe*, u32 addr, int P2);
void sqlite3VdbeChangeP3(Vdbe*, u32 addr, int P3);
void sqlite3VdbeChangeP5(Vdbe*, u8 P5);

Changes to src/vdbeInt.h.

85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
  VdbeSorter *pSorter;  /* Sorter object for OP_SorterOpen cursors */
  VdbeCursor *pAltCursor; /* Associated index cursor from which to read */
  int *aAltMap;           /* Mapping from table to index column numbers */
#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
  u64 maskUsed;         /* Mask of columns used by this cursor */
#endif

  /* Cached information about the header for the data record that the
  ** cursor is currently pointing to.  Only valid if cacheStatus matches
  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
  ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
  ** the cache is out of date.
  **
  ** aRow might point to (ephemeral) data for the current row, or it might







<







85
86
87
88
89
90
91

92
93
94
95
96
97
98
  i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
  VdbeSorter *pSorter;  /* Sorter object for OP_SorterOpen cursors */
  VdbeCursor *pAltCursor; /* Associated index cursor from which to read */
  int *aAltMap;           /* Mapping from table to index column numbers */
#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
  u64 maskUsed;         /* Mask of columns used by this cursor */
#endif

  /* Cached information about the header for the data record that the
  ** cursor is currently pointing to.  Only valid if cacheStatus matches
  ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
  ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
  ** the cache is out of date.
  **
  ** aRow might point to (ephemeral) data for the current row, or it might

Changes to src/vdbeaux.c.

217
218
219
220
221
222
223

















224
225
226
227
228
229
230
  const char *zP4,    /* The P4 operand */
  int p4type          /* P4 operand type */
){
  int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
  sqlite3VdbeChangeP4(p, addr, zP4, p4type);
  return addr;
}


















/*
** Add an OP_ParseSchema opcode.  This routine is broken out from
** sqlite3VdbeAddOp4() since it needs to also needs to mark all btrees
** as having been used.
**
** The zWhere string must have been obtained from sqlite3_malloc().







>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
  const char *zP4,    /* The P4 operand */
  int p4type          /* P4 operand type */
){
  int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
  sqlite3VdbeChangeP4(p, addr, zP4, p4type);
  return addr;
}

/*
** Add an opcode that includes the p4 value with a P4_INT64 type.
*/
int sqlite3VdbeAddOp4Dup8(
  Vdbe *p,            /* Add the opcode to this VM */
  int op,             /* The new opcode */
  int p1,             /* The P1 operand */
  int p2,             /* The P2 operand */
  int p3,             /* The P3 operand */
  const u8 *zP4,      /* The P4 operand */
  int p4type          /* P4 operand type */
){
  char *p4copy = sqlite3DbMallocRaw(sqlite3VdbeDb(p), 8);
  if( p4copy ) memcpy(p4copy, zP4, 8);
  return sqlite3VdbeAddOp4(p, op, p1, p2, p3, p4copy, p4type);
}

/*
** Add an OP_ParseSchema opcode.  This routine is broken out from
** sqlite3VdbeAddOp4() since it needs to also needs to mark all btrees
** as having been used.
**
** The zWhere string must have been obtained from sqlite3_malloc().

Changes to src/where.c.

6887
6888
6889
6890
6891
6892
6893




6894
6895
6896
6897
6898
6899
6900
....
6932
6933
6934
6935
6936
6937
6938















6939
6940
6941
6942
6943
6944
6945
        Bitmask b = pTabItem->colUsed;
        int n = 0;
        for(; b; b=b>>1, n++){}
        sqlite3VdbeChangeP4(v, sqlite3VdbeCurrentAddr(v)-1, 
                            SQLITE_INT_TO_PTR(n), P4_INT32);
        assert( n<=pTab->nCol );
      }




    }else{
      sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
    }
    if( pLoop->wsFlags & WHERE_INDEXED ){
      Index *pIx = pLoop->u.btree.pIndex;
      int iIndexCur;
      int op = OP_OpenRead;
................................................................................
        if( (pLoop->wsFlags & WHERE_CONSTRAINT)!=0
         && (pLoop->wsFlags & (WHERE_COLUMN_RANGE|WHERE_SKIPSCAN))==0
         && (pWInfo->wctrlFlags&WHERE_ORDERBY_MIN)==0
        ){
          sqlite3VdbeChangeP5(v, OPFLAG_SEEKEQ); /* Hint to COMDB2 */
        }
        VdbeComment((v, "%s", pIx->zName));















      }
    }
    if( iDb>=0 ) sqlite3CodeVerifySchema(pParse, iDb);
    notReady &= ~getMask(&pWInfo->sMaskSet, pTabItem->iCursor);
  }
  pWInfo->iTop = sqlite3VdbeCurrentAddr(v);
  if( db->mallocFailed ) goto whereBeginError;







>
>
>
>







 







>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







6887
6888
6889
6890
6891
6892
6893
6894
6895
6896
6897
6898
6899
6900
6901
6902
6903
6904
....
6936
6937
6938
6939
6940
6941
6942
6943
6944
6945
6946
6947
6948
6949
6950
6951
6952
6953
6954
6955
6956
6957
6958
6959
6960
6961
6962
6963
6964
        Bitmask b = pTabItem->colUsed;
        int n = 0;
        for(; b; b=b>>1, n++){}
        sqlite3VdbeChangeP4(v, sqlite3VdbeCurrentAddr(v)-1, 
                            SQLITE_INT_TO_PTR(n), P4_INT32);
        assert( n<=pTab->nCol );
      }
#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
      sqlite3VdbeAddOp4Dup8(v, OP_ColumnsUsed, pTabItem->iCursor, 0, 0,
                            (const u8*)&pTabItem->colUsed, P4_INT64);
#endif
    }else{
      sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
    }
    if( pLoop->wsFlags & WHERE_INDEXED ){
      Index *pIx = pLoop->u.btree.pIndex;
      int iIndexCur;
      int op = OP_OpenRead;
................................................................................
        if( (pLoop->wsFlags & WHERE_CONSTRAINT)!=0
         && (pLoop->wsFlags & (WHERE_COLUMN_RANGE|WHERE_SKIPSCAN))==0
         && (pWInfo->wctrlFlags&WHERE_ORDERBY_MIN)==0
        ){
          sqlite3VdbeChangeP5(v, OPFLAG_SEEKEQ); /* Hint to COMDB2 */
        }
        VdbeComment((v, "%s", pIx->zName));
#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
        {
          u64 colUsed = 0;
          int ii, jj;
          for(ii=0; ii<pIx->nColumn; ii++){
            jj = pIx->aiColumn[ii];
            if( jj<0 ) continue;
            if( jj>63 ) jj = 63;
            if( (pTabItem->colUsed & MASKBIT(jj))==0 ) continue;
            colUsed |= ((u64)1)<<(ii<63 ? ii : 63);
          }
          sqlite3VdbeAddOp4Dup8(v, OP_ColumnsUsed, iIndexCur, 0, 0,
                                (u8*)&colUsed, P4_INT64);
        }
#endif /* SQLITE_ENABLE_COLUMN_USED_MASK */
      }
    }
    if( iDb>=0 ) sqlite3CodeVerifySchema(pParse, iDb);
    notReady &= ~getMask(&pWInfo->sMaskSet, pTabItem->iCursor);
  }
  pWInfo->iTop = sqlite3VdbeCurrentAddr(v);
  if( db->mallocFailed ) goto whereBeginError;