Experimental changes to improve optimization of DISTINCT queries.
FossilOrigin-Name: f7ba0219ef2f235543c258be736955d91ca5ecce
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 09f64b7..c1e055b 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1966,6 +1966,7 @@
u16 wctrlFlags; /* Flags originally passed to sqlite3WhereBegin() */
u8 okOnePass; /* Ok to use one-pass algorithm for UPDATE or DELETE */
u8 untestedTerms; /* Not all WHERE terms resolved by outer loop */
+ u8 eDistinct;
SrcList *pTabList; /* List of tables in the join */
int iTop; /* The very beginning of the WHERE loop */
int iContinue; /* Jump here to continue with next record */
@@ -1977,6 +1978,9 @@
WhereLevel a[1]; /* Information about each nest loop in WHERE */
};
+#define WHERE_DISTINCT_UNIQUE 1
+#define WHERE_DISTINCT_ORDERED 2
+
/*
** A NameContext defines a context in which to resolve table and column
** names. The context consists of a list of tables (the pSrcList) field and
@@ -2738,7 +2742,7 @@
#endif
void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
-WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**, u16);
+WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**,ExprList*,u16);
void sqlite3WhereEnd(WhereInfo*);
int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int);
void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);