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Overview
| Comment: | Small changes to the OP_OpenEphemeral opcode to improve testability. |
|---|---|
| Downloads: | Tarball | ZIP archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA3-256: |
f856676c8438dbf52d299e78f6dd6148 |
| User & Date: | drh 2018-12-31 17:58:05.349 |
Context
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2018-12-31
| ||
| 20:39 | Additional steps to help ensure that scalar subqueries are only evaluated once even if they are used in multiple places within the query. This fixes a performance regression reported on the mailing list and caused by check-in [531eca6104e41e43] which was a fix for ticket [787fa716be3a7f650c]. Think of this check-in as an improved fix for that ticket. (check-in: e130319317 user: drh tags: trunk) | |
| 18:30 | Merge enhancements and bug fixes from trunk. (check-in: 9fb646f29c user: drh tags: reuse-subqueries) | |
| 17:58 | Small changes to the OP_OpenEphemeral opcode to improve testability. (check-in: f856676c84 user: drh tags: trunk) | |
| 16:36 | Fix the OP_OpenEphemeral opcode in the bytecode engine so that if it is called a second or subsequent time, it merely clears the existing table rather than creating a new one. Proposed fix for ticket [d0866b26f83e9c55e30de0821f5d]. (check-in: 4678cb1044 user: drh tags: trunk) | |
Changes
Changes to src/vdbe.c.
| ︙ | ︙ | |||
3663 3664 3665 3666 3667 3668 3669 |
assert( pOp->p1>=0 );
assert( pOp->p2>=0 );
pCx = p->apCsr[pOp->p1];
if( pCx ){
/* If the ephermeral table is already open, erase all existing content
** so that the table is empty again, rather than creating a new table. */
rc = sqlite3BtreeClearTable(pCx->pBtx, pCx->pgnoRoot, 0);
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assert( pOp->p1>=0 );
assert( pOp->p2>=0 );
pCx = p->apCsr[pOp->p1];
if( pCx ){
/* If the ephermeral table is already open, erase all existing content
** so that the table is empty again, rather than creating a new table. */
rc = sqlite3BtreeClearTable(pCx->pBtx, pCx->pgnoRoot, 0);
}else{
pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, CURTYPE_BTREE);
if( pCx==0 ) goto no_mem;
pCx->nullRow = 1;
pCx->isEphemeral = 1;
rc = sqlite3BtreeOpen(db->pVfs, 0, db, &pCx->pBtx,
BTREE_OMIT_JOURNAL | BTREE_SINGLE | pOp->p5,
vfsFlags);
if( rc==SQLITE_OK ){
rc = sqlite3BtreeBeginTrans(pCx->pBtx, 1, 0);
}
if( rc==SQLITE_OK ){
/* If a transient index is required, create it by calling
** sqlite3BtreeCreateTable() with the BTREE_BLOBKEY flag before
** opening it. If a transient table is required, just use the
** automatically created table with root-page 1 (an BLOB_INTKEY table).
*/
if( (pCx->pKeyInfo = pKeyInfo = pOp->p4.pKeyInfo)!=0 ){
assert( pOp->p4type==P4_KEYINFO );
rc = sqlite3BtreeCreateTable(pCx->pBtx, (int*)&pCx->pgnoRoot,
BTREE_BLOBKEY | pOp->p5);
if( rc==SQLITE_OK ){
assert( pCx->pgnoRoot==MASTER_ROOT+1 );
assert( pKeyInfo->db==db );
assert( pKeyInfo->enc==ENC(db) );
rc = sqlite3BtreeCursor(pCx->pBtx, pCx->pgnoRoot, BTREE_WRCSR,
pKeyInfo, pCx->uc.pCursor);
}
pCx->isTable = 0;
}else{
pCx->pgnoRoot = MASTER_ROOT;
rc = sqlite3BtreeCursor(pCx->pBtx, MASTER_ROOT, BTREE_WRCSR,
0, pCx->uc.pCursor);
pCx->isTable = 1;
}
}
pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
}
if( rc ) goto abort_due_to_error;
break;
}
/* Opcode: SorterOpen P1 P2 P3 P4 *
**
** This opcode works like OP_OpenEphemeral except that it opens
** a transient index that is specifically designed to sort large
|
| ︙ | ︙ |