Start of experimental implementation of SQL window functions. Does not yet
work.
FossilOrigin-Name: 3781e520854808fe02ad3fe77dd11fc917448c58ff1fd79123289dd91937decd
diff --git a/src/expr.c b/src/expr.c
index 6aff83a..a1407a8 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -1063,6 +1063,9 @@
}else{
sqlite3ExprListDelete(db, p->x.pList);
}
+ if( !ExprHasProperty(p, EP_Reduced) ){
+ sqlite3WindowDelete(db, p->pWin);
+ }
}
if( ExprHasProperty(p, EP_MemToken) ) sqlite3DbFree(db, p->u.zToken);
if( !ExprHasProperty(p, EP_Static) ){
@@ -1305,6 +1308,24 @@
# define withDup(x,y) 0
#endif
+static Window *winDup(sqlite3 *db, Window *p){
+ Window *pNew = 0;
+ if( p ){
+ pNew = sqlite3DbMallocZero(db, sizeof(Window));
+ if( pNew ){
+ pNew->pFilter = sqlite3ExprDup(db, p->pFilter, 0);
+ pNew->pPartition = sqlite3ExprListDup(db, p->pPartition, 0);
+ pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy, 0);
+ pNew->eType = p->eType;
+ pNew->eEnd = p->eEnd;
+ pNew->eStart = p->eStart;
+ pNew->pStart = sqlite3ExprDup(db, pNew->pStart, 0);
+ pNew->pEnd = sqlite3ExprDup(db, pNew->pEnd, 0);
+ }
+ }
+ return pNew;
+}
+
/*
** The following group of routines make deep copies of expressions,
** expression lists, ID lists, and select statements. The copies can
@@ -1469,6 +1490,7 @@
pNew->addrOpenEphm[1] = -1;
pNew->nSelectRow = p->nSelectRow;
pNew->pWith = withDup(db, p->pWith);
+ pNew->pWin = winDup(db, p->pWin);
sqlite3SelectSetName(pNew, p->zSelName);
*pp = pNew;
pp = &pNew->pPrior;
@@ -3778,6 +3800,10 @@
u8 enc = ENC(db); /* The text encoding used by this database */
CollSeq *pColl = 0; /* A collating sequence */
+ if( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) && pExpr->pWin ){
+ return pExpr->pWin->regResult;
+ }
+
if( ConstFactorOk(pParse) && sqlite3ExprIsConstantNotJoin(pExpr) ){
/* SQL functions can be expensive. So try to move constant functions
** out of the inner loop, even if that means an extra OP_Copy. */
@@ -3798,7 +3824,7 @@
pDef = sqlite3FindFunction(db, "unknown", nFarg, enc, 0);
}
#endif
- if( pDef==0 || pDef->xFinalize!=0 ){
+ if( pDef==0 /* || pDef->xFinalize!=0 */ ){
sqlite3ErrorMsg(pParse, "unknown function: %s()", zId);
break;
}