SQLite

Check-in [eab4297577]
Login

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

Overview
Comment:Use the OP_Sequence opcode for generating unique rowid values for an autoindex on a co-routine implementation of a subquery.
Downloads: Tarball | ZIP archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA3-256: eab4297577e4d325fed4757867fc77860de7448998d86f098c8a50272e17d35e
User & Date: drh 2019-06-28 07:08:13.998
Context
2019-07-02
20:10
Have ALTER TABLE detect and error out for the case where renaming a column changes a the interpretation of a double-quoted identifier in the database schema from an SQL literal to a column reference. (check-in: 5dbb0734af user: dan tags: tkt9b78184b-alt)
12:23
Restore the legacy behavior of enabling double-quoted string literals in all contexts. But also provide a new compile-time option (SQLITE_DQS) to change the default to something more restrictive. (check-in: 97a94446f3 user: drh tags: trunk)
11:56
Experimental implementation of FILTER clause for aggregate functions. (check-in: 1f1ae2d6ac user: dan tags: filter-clause)
2019-06-28
07:08
Use the OP_Sequence opcode for generating unique rowid values for an autoindex on a co-routine implementation of a subquery. (check-in: eab4297577 user: drh tags: trunk)
2019-06-26
21:04
Ensure that when an ephemeral cursor is reopened with a second invocation of to OP_OpenEphemeral, the sequence counter is reset and the cache marked as stale. Fix for [9cdc5c46]. (check-in: 5fd20e09a5 user: dan tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/where.c.
︙︙
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600

/*
** Convert OP_Column opcodes to OP_Copy in previously generated code.
**
** This routine runs over generated VDBE code and translates OP_Column
** opcodes into OP_Copy when the table is being accessed via co-routine 
** instead of via table lookup.
**
** If the bIncrRowid parameter is 0, then any OP_Rowid instructions on
** cursor iTabCur are transformed into OP_Null. Or, if bIncrRowid is non-zero,
** then each OP_Rowid is transformed into an instruction to increment the
** value stored in its output register.
*/
static void translateColumnToCopy(
  Parse *pParse,      /* Parsing context */
  int iStart,         /* Translate from this opcode to the end */
  int iTabCur,        /* OP_Column/OP_Rowid references to this table */
  int iRegister,      /* The first column is in this register */
  int bIncrRowid      /* If non-zero, transform OP_rowid to OP_AddImm(1) */
){
  Vdbe *v = pParse->pVdbe;
  VdbeOp *pOp = sqlite3VdbeGetOp(v, iStart);
  int iEnd = sqlite3VdbeCurrentAddr(v);
  if( pParse->db->mallocFailed ) return;
  for(; iStart<iEnd; iStart++, pOp++){
    if( pOp->p1!=iTabCur ) continue;
    if( pOp->opcode==OP_Column ){
      pOp->opcode = OP_Copy;
      pOp->p1 = pOp->p2 + iRegister;
      pOp->p2 = pOp->p3;
      pOp->p3 = 0;
    }else if( pOp->opcode==OP_Rowid ){
      if( bIncrRowid ){
        /* Increment the value stored in the P2 operand of the OP_Rowid. */
        pOp->opcode = OP_AddImm;
        pOp->p1 = pOp->p2;
        pOp->p2 = 1;
      }else{
        pOp->opcode = OP_Null;
        pOp->p1 = 0;
        pOp->p3 = 0;
      }
    }
  }








|
|
|
|






|













|
<
|
|
<








558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589

590
591

592
593
594
595
596
597
598

/*
** Convert OP_Column opcodes to OP_Copy in previously generated code.
**
** This routine runs over generated VDBE code and translates OP_Column
** opcodes into OP_Copy when the table is being accessed via co-routine 
** instead of via table lookup.
**
** If the iAutoidxCur is not zero, then any OP_Rowid instructions on
** cursor iTabCur are transformed into OP_Sequence opcode for the
** iAutoidxCur cursor, in order to generate unique rowids for the
** automatic index being generated.
*/
static void translateColumnToCopy(
  Parse *pParse,      /* Parsing context */
  int iStart,         /* Translate from this opcode to the end */
  int iTabCur,        /* OP_Column/OP_Rowid references to this table */
  int iRegister,      /* The first column is in this register */
  int iAutoidxCur     /* If non-zero, cursor of autoindex being generated */
){
  Vdbe *v = pParse->pVdbe;
  VdbeOp *pOp = sqlite3VdbeGetOp(v, iStart);
  int iEnd = sqlite3VdbeCurrentAddr(v);
  if( pParse->db->mallocFailed ) return;
  for(; iStart<iEnd; iStart++, pOp++){
    if( pOp->p1!=iTabCur ) continue;
    if( pOp->opcode==OP_Column ){
      pOp->opcode = OP_Copy;
      pOp->p1 = pOp->p2 + iRegister;
      pOp->p2 = pOp->p3;
      pOp->p3 = 0;
    }else if( pOp->opcode==OP_Rowid ){
      if( iAutoidxCur ){

        pOp->opcode = OP_Sequence;
        pOp->p1 = iAutoidxCur;

      }else{
        pOp->opcode = OP_Null;
        pOp->p1 = 0;
        pOp->p3 = 0;
      }
    }
  }
︙︙
860
861
862
863
864
865
866

867
868
869
870
871
872
873
874
875

  );
  sqlite3VdbeAddOp2(v, OP_IdxInsert, pLevel->iIdxCur, regRecord);
  sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
  if( pPartial ) sqlite3VdbeResolveLabel(v, iContinue);
  if( pTabItem->fg.viaCoroutine ){
    sqlite3VdbeChangeP2(v, addrCounter, regBase+n);
    testcase( pParse->db->mallocFailed );

    translateColumnToCopy(pParse, addrTop, pLevel->iTabCur,
                          pTabItem->regResult, 1);
    sqlite3VdbeGoto(v, addrTop);
    pTabItem->fg.viaCoroutine = 0;
  }else{
    sqlite3VdbeAddOp2(v, OP_Next, pLevel->iTabCur, addrTop+1); VdbeCoverage(v);
  }
  sqlite3VdbeChangeP5(v, SQLITE_STMTSTATUS_AUTOINDEX);
  sqlite3VdbeJumpHere(v, addrTop);








>

|








858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874

  );
  sqlite3VdbeAddOp2(v, OP_IdxInsert, pLevel->iIdxCur, regRecord);
  sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
  if( pPartial ) sqlite3VdbeResolveLabel(v, iContinue);
  if( pTabItem->fg.viaCoroutine ){
    sqlite3VdbeChangeP2(v, addrCounter, regBase+n);
    testcase( pParse->db->mallocFailed );
    assert( pLevel->iIdxCur>0 );
    translateColumnToCopy(pParse, addrTop, pLevel->iTabCur,
                          pTabItem->regResult, pLevel->iIdxCur);
    sqlite3VdbeGoto(v, addrTop);
    pTabItem->fg.viaCoroutine = 0;
  }else{
    sqlite3VdbeAddOp2(v, OP_Next, pLevel->iTabCur, addrTop+1); VdbeCoverage(v);
  }
  sqlite3VdbeChangeP5(v, SQLITE_STMTSTATUS_AUTOINDEX);
  sqlite3VdbeJumpHere(v, addrTop);
︙︙
Changes to test/autoindex5.test.
︙︙
119
120
121
122
123
124
125














126
127
128
129
130
131
132

    UNION ALL
    SELECT 0, 0 WHERE 0;

  SELECT (
      SELECT sum(z) FROM vvv WHERE x='aaa'
  ) FROM one;
} {8.0}















# Ticket https://www.sqlite.org/src/info/787fa716be3a7f65
# Segfault due to multiple uses of the same subquery where the
# subquery is implemented via coroutine.
#
ifcapable windowfunc {
sqlite3 db :memory:








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








119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146

    UNION ALL
    SELECT 0, 0 WHERE 0;

  SELECT (
      SELECT sum(z) FROM vvv WHERE x='aaa'
  ) FROM one;
} {8.0}
do_execsql_test 2.2 {
  DROP TABLE t1;
  CREATE TABLE t1(aaa);
  INSERT INTO t1(aaa) VALUES(9);
  SELECT (
    SELECT aaa FROM t1 GROUP BY (
      SELECT bbb FROM (
        SELECT ccc AS bbb FROM (
           SELECT 1 ccc
        ) WHERE rowid IS NOT 1
      ) WHERE bbb = 1
    )
  );
} {9}

# Ticket https://www.sqlite.org/src/info/787fa716be3a7f65
# Segfault due to multiple uses of the same subquery where the
# subquery is implemented via coroutine.
#
ifcapable windowfunc {
sqlite3 db :memory:
︙︙