database/sqlite
1
0
Fork 0
mirror of https://github.com/sqlite/sqlite.git synced 2025-11-08 03:22:21 +03:00
Code Activity

Add the ability to disable constant factoring using sqlite3_test_control().

Browse Source 
Add a TCL interface to this new capability and add tests cases to the TCL
test scripts to actually use the new capability.

FossilOrigin-Name: ad8bc68197f2b47435149c3dbc035f4e7210fc76
This commit is contained in:
drh
2010-12-06 21:06:09 +00:00
parent ef4c059843
commit f58ee7f1aa
6 changed files with 129 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
src/expr.c
View File

@@ -3040,10 +3040,22 @@ static int evalConstExpr(Walker *pWalker, Expr *pExpr){
** Preevaluate constant subexpressions within pExpr and store the
** results in registers. Modify pExpr so that the constant subexpresions
** are TK_REGISTER opcodes that refer to the precomputed values.
**
** This routine is a no-op if the jump to the cookie-check code has
** already occur. Since the cookie-check jump is generated prior to
** any other serious processing, this check ensures that there is no
** way to accidently bypass the constant initializations.
**
** This routine is also a no-op if the SQLITE_FactorOutConst optimization
** is disabled via the sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS)
** interface. This allows test logic to verify that the same answer is
** obtained for queries regardless of whether or not constants are
** precomputed into registers or if they are inserted in-line.
*/
void sqlite3ExprCodeConstants(Parse *pParse, Expr *pExpr){
Walker w;
if( pParse->cookieGoto ) return;
if( (pParse->db->flags & SQLITE_FactorOutConst)!=0 ) return;
w.xExprCallback = evalConstExpr;
w.xSelectCallback = 0;
w.pParse = pParse;