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Overview
Comment: | Use the OP_Sequence opcode for generating unique rowid values for an autoindex on a co-routine implementation of a subquery. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA3-256: |
eab4297577e4d325fed4757867fc7786 |
User & Date: | drh 2019-06-28 07:08:13.998 |
Context
2019-07-02
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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
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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
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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
Changes to src/where.c.
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558 559 560 561 562 563 564 | /* ** 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. ** | | | | | | | < | | < | 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; } } } |
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860 861 862 863 864 865 866 867 | ); 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, | > | | 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); |
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Changes to test/autoindex5.test.
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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: |
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