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Overview
Comment: | Slight performance improvement in the OP_Column opcode. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
5c157474391f90f24e8867c77fbc6564 |
User & Date: | drh 2016-05-20 19:51:28.931 |
Context
2016-05-20
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20:58 | Fix typo in comment. (check-in: 9db8f21473 user: mistachkin tags: trunk) | |
19:51 | Slight performance improvement in the OP_Column opcode. (check-in: 5c15747439 user: drh tags: trunk) | |
18:09 | Remove the sqlite3PagerClearCache() routine, which does not accomplish anything useful. (check-in: f250166bb3 user: drh tags: trunk) | |
Changes
Changes to src/vdbe.c.
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2571 2572 2573 2574 2575 2576 2577 | /* Extract the content for the p2+1-th column. Control can only ** reach this point if aOffset[p2], aOffset[p2+1], and pC->aType[p2] are ** all valid. */ assert( p2<pC->nHdrParsed ); assert( rc==SQLITE_OK ); assert( sqlite3VdbeCheckMemInvariants(pDest) ); | | > > < > > | 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 | /* Extract the content for the p2+1-th column. Control can only ** reach this point if aOffset[p2], aOffset[p2+1], and pC->aType[p2] are ** all valid. */ assert( p2<pC->nHdrParsed ); assert( rc==SQLITE_OK ); assert( sqlite3VdbeCheckMemInvariants(pDest) ); if( VdbeMemDynamic(pDest) ){ sqlite3VdbeMemSetNull(pDest); } assert( t==pC->aType[p2] ); if( pC->szRow>=aOffset[p2+1] ){ /* This is the common case where the desired content fits on the original ** page - where the content is not on an overflow page */ zData = pC->aRow + aOffset[p2]; if( t<12 ){ sqlite3VdbeSerialGet(zData, t, pDest); }else{ /* If the column value is a string, we need a persistent value, not ** a MEM_Ephem value. This branch is a fast short-cut that is equivalent ** to calling sqlite3VdbeSerialGet() and sqlite3VdbeDeephemeralize(). */ static const u16 aFlag[] = { MEM_Blob, MEM_Str|MEM_Term }; pDest->n = len = (t-12)/2; pDest->enc = encoding; if( pDest->szMalloc < len+2 ){ pDest->flags = MEM_Null; if( sqlite3VdbeMemGrow(pDest, len+2, 0) ) goto no_mem; }else{ pDest->z = pDest->zMalloc; } memcpy(pDest->z, zData, len); pDest->z[len] = 0; pDest->z[len+1] = 0; pDest->flags = aFlag[t&1]; } }else{ pDest->enc = encoding; /* This branch happens only when content is on overflow pages */ if( ((pOp->p5 & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG))!=0 && ((t>=12 && (t&1)==0) || (pOp->p5 & OPFLAG_TYPEOFARG)!=0)) || (len = sqlite3VdbeSerialTypeLen(t))==0 ){ /* Content is irrelevant for ** 1. the typeof() function, |
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