/ Check-in [a73f80f2]
Login

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

Overview
Comment:Document the dual-use of the P5 operand to the OP_MakeRecord opcode.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA3-256: a73f80f22a585d1a2f55650d5cda4ece6c4ef039ef5eae2c02c3e5c269d4c30a
User & Date: drh 2020-06-29 20:09:04
Context
2020-06-29
20:20
Change the magic number used to identify the "excluded" pseudo-table in an UPSERT statement into a #define constant. (check-in: e96c2ac9 user: drh tags: trunk)
20:09
Document the dual-use of the P5 operand to the OP_MakeRecord opcode. (check-in: a73f80f2 user: drh tags: trunk)
18:30
Change the name of IntegrityCk.mallocFailed to IntegrityCk.bOomFault to avoid confusion with the sqlite3 object field with the same name. (check-in: 87c7d962 user: drh tags: trunk)
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/update.c.

1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
    sqlite3VdbeChangeToNoop(v, addr);
    sqlite3VdbeAddOp1(v, OP_Close, iCsr);
  }else{
    /* Create a record from the argument register contents and insert it into
    ** the ephemeral table. */
    sqlite3MultiWrite(pParse);
    sqlite3VdbeAddOp3(v, OP_MakeRecord, regArg, nArg, regRec);
#ifdef SQLITE_DEBUG
    /* Signal an assert() within OP_MakeRecord that it is allowed to
    ** accept no-change records with serial_type 10 */
    sqlite3VdbeChangeP5(v, OPFLAG_NOCHNG_MAGIC);
#endif
    sqlite3VdbeAddOp2(v, OP_NewRowid, ephemTab, regRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, ephemTab, regRec, regRowid);
  }







|







1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
    sqlite3VdbeChangeToNoop(v, addr);
    sqlite3VdbeAddOp1(v, OP_Close, iCsr);
  }else{
    /* Create a record from the argument register contents and insert it into
    ** the ephemeral table. */
    sqlite3MultiWrite(pParse);
    sqlite3VdbeAddOp3(v, OP_MakeRecord, regArg, nArg, regRec);
#if defined(SQLITE_DEBUG) && !defined(SQLITE_ENABLE_NULL_TRIM)
    /* Signal an assert() within OP_MakeRecord that it is allowed to
    ** accept no-change records with serial_type 10 */
    sqlite3VdbeChangeP5(v, OPFLAG_NOCHNG_MAGIC);
#endif
    sqlite3VdbeAddOp2(v, OP_NewRowid, ephemTab, regRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, ephemTab, regRec, regRowid);
  }

Changes to src/vdbe.c.

2918
2919
2920
2921
2922
2923
2924











2925
2926
2927
2928
2929
2930
2931
....
3036
3037
3038
3039
3040
3041
3042

3043

3044
3045
3046
3047
3048
3049
3050
** string indicates the column affinity that should be used for the N-th
** field of the index key.
**
** The mapping from character to affinity is given by the SQLITE_AFF_
** macros defined in sqliteInt.h.
**
** If P4 is NULL then all index fields have the affinity BLOB.











*/
case OP_MakeRecord: {
  Mem *pRec;             /* The new record */
  u64 nData;             /* Number of bytes of data space */
  int nHdr;              /* Number of bytes of header space */
  i64 nByte;             /* Data space required for this record */
  i64 nZero;             /* Number of zero bytes at the end of the record */
................................................................................
      if( pRec->flags & MEM_Zero ){
        /* Values with MEM_Null and MEM_Zero are created by xColumn virtual
        ** table methods that never invoke sqlite3_result_xxxxx() while
        ** computing an unchanging column value in an UPDATE statement.
        ** Give such values a special internal-use-only serial-type of 10
        ** so that they can be passed through to xUpdate and have
        ** a true sqlite3_value_nochange(). */

        assert( pOp->p5==OPFLAG_NOCHNG_MAGIC || CORRUPT_DB );

        pRec->uTemp = 10;
      }else{
        pRec->uTemp = 0;
      }
      nHdr++;
    }else if( pRec->flags & (MEM_Int|MEM_IntReal) ){
      /* Figure out whether to use 1, 2, 4, 6 or 8 bytes. */







>
>
>
>
>
>
>
>
>
>
>







 







>

>







2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
....
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
** string indicates the column affinity that should be used for the N-th
** field of the index key.
**
** The mapping from character to affinity is given by the SQLITE_AFF_
** macros defined in sqliteInt.h.
**
** If P4 is NULL then all index fields have the affinity BLOB.
**
** The meaning of P5 depends on whether or not the SQLITE_ENABLE_NULL_TRIM
** compile-time option is enabled:
**
**   * If SQLITE_ENABLE_NULL_TRIM is enabled, then the P5 is the index
**     of the right-most table that can be null-trimmed.
**
**   * If SQLITE_ENABLE_NULL_TRIM is omitted, then P5 has the value
**     OPFLAG_NOCHNG_MAGIC if the OP_MakeRecord opcode is allowed to
**     accept no-change records with serial_type 10.  This value is
**     only used inside an assert() and does not affect the end result.
*/
case OP_MakeRecord: {
  Mem *pRec;             /* The new record */
  u64 nData;             /* Number of bytes of data space */
  int nHdr;              /* Number of bytes of header space */
  i64 nByte;             /* Data space required for this record */
  i64 nZero;             /* Number of zero bytes at the end of the record */
................................................................................
      if( pRec->flags & MEM_Zero ){
        /* Values with MEM_Null and MEM_Zero are created by xColumn virtual
        ** table methods that never invoke sqlite3_result_xxxxx() while
        ** computing an unchanging column value in an UPDATE statement.
        ** Give such values a special internal-use-only serial-type of 10
        ** so that they can be passed through to xUpdate and have
        ** a true sqlite3_value_nochange(). */
#ifndef SQLITE_ENABLE_NULL_TRIM
        assert( pOp->p5==OPFLAG_NOCHNG_MAGIC || CORRUPT_DB );
#endif
        pRec->uTemp = 10;
      }else{
        pRec->uTemp = 0;
      }
      nHdr++;
    }else if( pRec->flags & (MEM_Int|MEM_IntReal) ){
      /* Figure out whether to use 1, 2, 4, 6 or 8 bytes. */