Use the VList object to replace Parse.azVar for tracking the mapping between
SQL parameter names and parameter numbers. There is a performance
improvement, though there are still a few hiccups in the current code.
FossilOrigin-Name: 68ecafa1425a41358c88f41efea3262f1b4490f2
diff --git a/src/expr.c b/src/expr.c
index 60843bf..ae61074 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -934,7 +934,7 @@
** variable number.
**
** Wildcards of the form "?nnn" are assigned the number "nnn". We make
-** sure "nnn" is not too be to avoid a denial of service attack when
+** sure "nnn" is not too big to avoid a denial of service attack when
** the SQL statement comes from an external source.
**
** Wildcards of the form ":aaa", "@aaa", or "$aaa" are assigned the same number
@@ -981,30 +981,13 @@
** number as the prior appearance of the same name, or if the name
** has never appeared before, reuse the same variable number
*/
- ynVar i;
- for(i=x=0; i<pParse->nzVar; i++){
- if( pParse->azVar[i] && strcmp(pParse->azVar[i],z)==0 ){
- x = (ynVar)i+1;
- break;
- }
+ x = (ynVar)sqlite3VListNameToNum(pParse->pVList, z, n);
+ if( x==0 ){
+ x = (ynVar)(++pParse->nVar);
+ pParse->pVList = sqlite3VListAdd(db, pParse->pVList, z, n, x);
}
- if( x==0 ) x = (ynVar)(++pParse->nVar);
}
pExpr->iColumn = x;
- if( x>pParse->nzVar ){
- char **a;
- a = sqlite3DbRealloc(db, pParse->azVar, x*sizeof(a[0]));
- if( a==0 ){
- assert( db->mallocFailed ); /* Error reported through mallocFailed */
- return;
- }
- pParse->azVar = a;
- memset(&a[pParse->nzVar], 0, (x-pParse->nzVar)*sizeof(a[0]));
- pParse->nzVar = x;
- }
- if( pParse->azVar[x-1]==0 ){
- pParse->azVar[x-1] = sqlite3DbStrNDup(db, z, n);
- }
}
if( pParse->nVar>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
sqlite3ErrorMsg(pParse, "too many SQL variables");
@@ -3430,9 +3413,11 @@
assert( pExpr->u.zToken[0]!=0 );
sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iColumn, target);
if( pExpr->u.zToken[1]!=0 ){
- assert( pExpr->u.zToken[0]=='?'
- || strcmp(pExpr->u.zToken, pParse->azVar[pExpr->iColumn-1])==0 );
- sqlite3VdbeAppendP4(v, pParse->azVar[pExpr->iColumn-1], P4_STATIC);
+ const char *z = sqlite3VListNumToName(pParse->pVList, pExpr->iColumn);
+ if( z ){
+ assert( pExpr->u.zToken[0]=='?' || strcmp(pExpr->u.zToken, z)==0 );
+ sqlite3VdbeAppendP4(v, (char*)z, P4_STATIC);
+ }
}
return target;
}