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Overview
Comment: | Improvements to opcode documentation in the bytecode engine. No changes to code. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA3-256: |
e54c9f8db5b2fa8ea82c6eab74822554 |
User & Date: | drh 2017-04-29 18:02:49.909 |
Context
2017-04-29
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19:29 | Add a single testcase() macro to the subquery processing logic. (check-in: 4e1df76e3d user: drh tags: trunk) | |
18:02 | Improvements to opcode documentation in the bytecode engine. No changes to code. (check-in: e54c9f8db5 user: drh tags: trunk) | |
15:27 | Evaluate WHERE clause terms that reference only the index before evaluating terms that require the table, and thereby avoid seeking the table row if index terms are false. This is called the "push-down" optimization in the MySQL world, we are told. Do not confuse with WHERE-clause push-down. (check-in: d7bb79ed3a user: drh tags: trunk) | |
Changes
Changes to src/vdbe.c.
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760 761 762 763 764 765 766 | ** to the current line should be indented for EXPLAIN output. */ case OP_Goto: { /* jump */ jump_to_p2_and_check_for_interrupt: pOp = &aOp[pOp->p2 - 1]; /* Opcodes that are used as the bottom of a loop (OP_Next, OP_Prev, | | | 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 | ** to the current line should be indented for EXPLAIN output. */ case OP_Goto: { /* jump */ jump_to_p2_and_check_for_interrupt: pOp = &aOp[pOp->p2 - 1]; /* Opcodes that are used as the bottom of a loop (OP_Next, OP_Prev, ** OP_VNext, or OP_SorterNext) all jump here upon ** completion. Check to see if sqlite3_interrupt() has been called ** or if the progress callback needs to be invoked. ** ** This code uses unstructured "goto" statements and does not look clean. ** But that is not due to sloppy coding habits. The code is written this ** way for performance, to avoid having to run the interrupt and progress ** checks on every opcode. This helps sqlite3_step() to run about 1.5% |
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1563 1564 1565 1566 1567 1568 1569 | arithmetic_result_is_null: sqlite3VdbeMemSetNull(pOut); break; } /* Opcode: CollSeq P1 * * P4 ** | | | 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 | arithmetic_result_is_null: sqlite3VdbeMemSetNull(pOut); break; } /* Opcode: CollSeq P1 * * P4 ** ** P4 is a pointer to a CollSeq object. If the next call to a user function ** or aggregate calls sqlite3GetFuncCollSeq(), this collation sequence will ** be returned. This is used by the built-in min(), max() and nullif() ** functions. ** ** If P1 is not zero, then it is a register that a subsequent min() or ** max() aggregate will set to 1 if the current row is not the minimum or ** maximum. The P1 register is initialized to 0 by this instruction. |
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1844 1845 1846 1847 1848 1849 1850 | #ifndef SQLITE_OMIT_CAST /* Opcode: Cast P1 P2 * * * ** Synopsis: affinity(r[P1]) ** ** Force the value in register P1 to be the type defined by P2. ** ** <ul> | | | | | | | 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 | #ifndef SQLITE_OMIT_CAST /* Opcode: Cast P1 P2 * * * ** Synopsis: affinity(r[P1]) ** ** Force the value in register P1 to be the type defined by P2. ** ** <ul> ** <li> P2=='A' → BLOB ** <li> P2=='B' → TEXT ** <li> P2=='C' → NUMERIC ** <li> P2=='D' → INTEGER ** <li> P2=='E' → REAL ** </ul> ** ** A NULL value is not changed by this routine. It remains NULL. */ case OP_Cast: { /* in1 */ assert( pOp->p2>=SQLITE_AFF_BLOB && pOp->p2<=SQLITE_AFF_REAL ); testcase( pOp->p2==SQLITE_AFF_TEXT ); |
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2719 2720 2721 2722 2723 2724 2725 | } /* Opcode: Affinity P1 P2 * P4 * ** Synopsis: affinity(r[P1@P2]) ** ** Apply affinities to a range of P2 registers starting with P1. ** | | | | 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 | } /* Opcode: Affinity P1 P2 * P4 * ** Synopsis: affinity(r[P1@P2]) ** ** Apply affinities to a range of P2 registers starting with P1. ** ** P4 is a string that is P2 characters long. The N-th character of the ** string indicates the column affinity that should be used for the N-th ** memory cell in the range. */ case OP_Affinity: { const char *zAffinity; /* The affinity to be applied */ zAffinity = pOp->p4.z; assert( zAffinity!=0 ); |
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2747 2748 2749 2750 2751 2752 2753 | /* Opcode: MakeRecord P1 P2 P3 P4 * ** Synopsis: r[P3]=mkrec(r[P1@P2]) ** ** Convert P2 registers beginning with P1 into the [record format] ** use as a data record in a database table or as a key ** in an index. The OP_Column opcode can decode the record later. ** | | | | 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 | /* Opcode: MakeRecord P1 P2 P3 P4 * ** Synopsis: r[P3]=mkrec(r[P1@P2]) ** ** Convert P2 registers beginning with P1 into the [record format] ** use as a data record in a database table or as a key ** in an index. The OP_Column opcode can decode the record later. ** ** P4 may be a string that is P2 characters long. The N-th character of the ** 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. */ |
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5744 5745 5746 5747 5748 5749 5750 | break; } #endif /* SQLITE_OMIT_INTEGRITY_CHECK */ /* Opcode: RowSetAdd P1 P2 * * * ** Synopsis: rowset(P1)=r[P2] ** | | | > | | 5744 5745 5746 5747 5748 5749 5750 5751 5752 5753 5754 5755 5756 5757 5758 5759 5760 5761 5762 5763 5764 5765 5766 5767 5768 5769 5770 5771 5772 5773 5774 5775 5776 5777 5778 5779 5780 | break; } #endif /* SQLITE_OMIT_INTEGRITY_CHECK */ /* Opcode: RowSetAdd P1 P2 * * * ** Synopsis: rowset(P1)=r[P2] ** ** Insert the integer value held by register P2 into a RowSet object ** held in register P1. ** ** An assertion fails if P2 is not an integer. */ case OP_RowSetAdd: { /* in1, in2 */ pIn1 = &aMem[pOp->p1]; pIn2 = &aMem[pOp->p2]; assert( (pIn2->flags & MEM_Int)!=0 ); if( (pIn1->flags & MEM_RowSet)==0 ){ sqlite3VdbeMemSetRowSet(pIn1); if( (pIn1->flags & MEM_RowSet)==0 ) goto no_mem; } sqlite3RowSetInsert(pIn1->u.pRowSet, pIn2->u.i); break; } /* Opcode: RowSetRead P1 P2 P3 * * ** Synopsis: r[P3]=rowset(P1) ** ** Extract the smallest value from the RowSet object in P1 ** and put that value into register P3. ** Or, if RowSet object P1 is initially empty, leave P3 ** unchanged and jump to instruction P2. */ case OP_RowSetRead: { /* jump, in1, out3 */ i64 val; pIn1 = &aMem[pOp->p1]; if( (pIn1->flags & MEM_RowSet)==0 |
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5796 5797 5798 5799 5800 5801 5802 | ** ** Register P3 is assumed to hold a 64-bit integer value. If register P1 ** contains a RowSet object and that RowSet object contains ** the value held in P3, jump to register P2. Otherwise, insert the ** integer in P3 into the RowSet and continue on to the ** next opcode. ** | | | | | < | | | 5797 5798 5799 5800 5801 5802 5803 5804 5805 5806 5807 5808 5809 5810 5811 5812 5813 5814 5815 5816 5817 5818 | ** ** Register P3 is assumed to hold a 64-bit integer value. If register P1 ** contains a RowSet object and that RowSet object contains ** the value held in P3, jump to register P2. Otherwise, insert the ** integer in P3 into the RowSet and continue on to the ** next opcode. ** ** The RowSet object is optimized for the case where sets of integers ** are inserted in distinct phases, which each set contains no duplicates. ** Each set is identified by a unique P4 value. The first set ** must have P4==0, the final set must have P4==-1, and for all other sets ** must have P4>0. ** ** This allows optimizations: (a) when P4==0 there is no need to test ** the RowSet object for P3, as it is guaranteed not to contain it, ** (b) when P4==-1 there is no need to insert the value, as it will ** never be tested for, and (c) when a value that is part of set X is ** inserted, there is no need to search to see if the same value was ** previously inserted as part of set X (only if it was previously ** inserted as part of some other set). */ case OP_RowSetTest: { /* jump, in1, in3 */ |
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