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Overview
| Comment: | Prevent the use of subroutines to implement the RHS of IN operators within CHECK constraints. |
|---|---|
| Downloads: | Tarball | ZIP archive |
| Timelines: | family | ancestors | descendants | both | reuse-subqueries |
| Files: | files | file ages | folders |
| SHA3-256: |
6b24d3fb94e787d25e49501714780dfb |
| User & Date: | drh 2018-12-24 11:55:44.935 |
Context
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2018-12-24
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| 12:09 | Do not generate subroutines for non-static SELECT and EXISTS expressions. Fix up some test cases to account for the minor changes in EXPLAIN QUERY PLAN output. (check-in: 06de44ec9e user: drh tags: reuse-subqueries) | |
| 11:55 | Prevent the use of subroutines to implement the RHS of IN operators within CHECK constraints. (check-in: 6b24d3fb94 user: drh tags: reuse-subqueries) | |
| 02:34 | Experimental code that tries to put the computation of subqueries inside a subroutine, and reuse that subroutine if the same subquery is evaluated more than once. Current code does not work for CHECK constraints. (check-in: 6c44838adb user: drh tags: reuse-subqueries) | |
Changes
Changes to src/expr.c.
| ︙ | ︙ | |||
2681 2682 2683 2684 2685 2686 2687 | ** * The right-hand side is a correlated subquery ** * The right-hand side is an expression list containing variables ** * We are inside a trigger ** ** If all of the above are false, then we can compute the RHS just once ** and reuse it many names. */ | | | 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 |
** * The right-hand side is a correlated subquery
** * The right-hand side is an expression list containing variables
** * We are inside a trigger
**
** If all of the above are false, then we can compute the RHS just once
** and reuse it many names.
*/
if( !ExprHasProperty(pExpr, EP_VarSelect) && pParse->iSelfTab==0 ){
/* Reuse of the RHS is allowed */
/* If this routine has already been coded, but the previous code
** might not have been invoked yet, so invoke it now as a subroutine.
*/
if( ExprHasProperty(pExpr, EP_Subrtn) ){
sqlite3VdbeAddOp2(v, OP_Once, 0, sqlite3VdbeCurrentAddr(v)+3);
sqlite3VdbeAddOp2(v, OP_Gosub, pExpr->y.sub.regReturn,
|
| ︙ | ︙ |