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Overview
Comment: | 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: |
4737cadc414c5f6d256fcceacb19d80d |
User & Date: | drh 2016-05-19 16:58:42.935 |
Context
2016-05-19
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17:51 | Optimization marks in vdbe.c. No logic changes. (check-in: cf2737415a user: drh tags: trunk) | |
16:58 | Performance improvement in the OP_Column opcode. (check-in: 4737cadc41 user: drh tags: trunk) | |
16:21 | Add test cases to test some fts3/4 edge case behaviour surrounding the '*' character. (check-in: 1f577e1f08 user: dan tags: trunk) | |
Changes
Changes to src/vdbe.c.
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2481 2482 2483 2484 2485 2486 2487 | ** 3-byte type for each of the maximum of 32768 columns plus three ** extra bytes for the header length itself. 32768*3 + 3 = 98307. */ if( offset > 98307 || offset > pC->payloadSize ){ rc = SQLITE_CORRUPT_BKPT; goto abort_due_to_error; } | < | > > < > < | 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 | ** 3-byte type for each of the maximum of 32768 columns plus three ** extra bytes for the header length itself. 32768*3 + 3 = 98307. */ if( offset > 98307 || offset > pC->payloadSize ){ rc = SQLITE_CORRUPT_BKPT; goto abort_due_to_error; } }else if( offset>0 ){ /*OPTIMIZATION-IF-TRUE*/ /* The following goto is an optimization. It can be omitted and ** everything will still work. But OP_Column is measurably faster ** by skipping the subsequent conditional, which is always true. */ zData = pC->aRow; assert( pC->nHdrParsed<=p2 ); /* Conditional skipped */ goto op_column_read_header; } } /* Make sure at least the first p2+1 entries of the header have been ** parsed and valid information is in aOffset[] and pC->aType[]. */ if( pC->nHdrParsed<=p2 ){ /* If there is more header available for parsing in the record, try ** to extract additional fields up through the p2+1-th field */ if( pC->iHdrOffset<aOffset[0] ){ /* Make sure zData points to enough of the record to cover the header. */ if( pC->aRow==0 ){ memset(&sMem, 0, sizeof(sMem)); rc = sqlite3VdbeMemFromBtree(pCrsr, 0, aOffset[0], !pC->isTable, &sMem); if( rc!=SQLITE_OK ) goto abort_due_to_error; zData = (u8*)sMem.z; }else{ zData = pC->aRow; } /* Fill in pC->aType[i] and aOffset[i] values through the p2-th field. */ op_column_read_header: i = pC->nHdrParsed; offset64 = aOffset[i]; zHdr = zData + pC->iHdrOffset; zEndHdr = zData + aOffset[0]; do{ if( (t = zHdr[0])<0x80 ){ zHdr++; offset64 += sqlite3VdbeOneByteSerialTypeLen(t); }else{ zHdr += sqlite3GetVarint32(zHdr, &t); offset64 += sqlite3VdbeSerialTypeLen(t); |
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