diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/select.c | 11 | ||||
| -rw-r--r-- | src/sqliteInt.h | 2 |
2 files changed, 11 insertions, 2 deletions
diff --git a/src/select.c b/src/select.c index 69a07528f..e546a664c 100644 --- a/src/select.c +++ b/src/select.c @@ -7421,7 +7421,14 @@ static void existsToJoin(Parse *pParse, Select *p, Expr *pWhere){ pSub->pWhere = 0; pSub->pSrc = 0; - sqlite3SelectDelete(pParse->db, pSub); + sqlite3ParserAddCleanup(pParse, sqlite3SelectDeleteGeneric, pSub); +#if TREETRACE_ENABLED + if( sqlite3TreeTrace & 0x100000 ){ + TREETRACE(0x100000,pParse,p, + ("After EXISTS-to-JOIN optimization:\n")); + sqlite3TreeViewSelect(0, p, 0); + } +#endif } } } @@ -7756,7 +7763,7 @@ int sqlite3Select( /* If there may be an "EXISTS (SELECT ...)" in the WHERE clause, attempt ** to change it into a join. */ - if( pParse->bHasExists ){ + if( pParse->bHasExists && OptimizationEnabled(db,SQLITE_ExistsToJoin) ){ existsToJoin(pParse, p, p->pWhere); pTabList = p->pSrc; } diff --git a/src/sqliteInt.h b/src/sqliteInt.h index c976b928d..6a1b22f92 100644 --- a/src/sqliteInt.h +++ b/src/sqliteInt.h @@ -1126,6 +1126,7 @@ extern u32 sqlite3TreeTrace; ** 0x00020000 Transform DISTINCT into GROUP BY ** 0x00040000 SELECT tree dump after all code has been generated ** 0x00080000 NOT NULL strength reduction +** 0x00100000 EXISTS-to-JOIN optimization */ /* @@ -1924,6 +1925,7 @@ struct sqlite3 { #define SQLITE_Coroutines 0x02000000 /* Co-routines for subqueries */ #define SQLITE_NullUnusedCols 0x04000000 /* NULL unused columns in subqueries */ #define SQLITE_OnePass 0x08000000 /* Single-pass DELETE and UPDATE */ +#define SQLITE_ExistsToJoin 0x10000000 /* The EXISTS-to-JOIN optimization */ #define SQLITE_AllOpts 0xffffffff /* All optimizations */ /* |