Update the parser so that sub-queries and CTEs may have WITH clauses.

FossilOrigin-Name: 704d3931b855562a619769955969d439c42ca406

src/build.c

@@ -4200,22 +4200,26 @@ KeyInfo *sqlite3KeyInfoOfIndex(Parse *pParse, Index *pIdx){
 }
 
 #ifndef SQLITE_OMIT_CTE
-/* This routine is invoked when a single with_query of a
-** common-table-expression has been parsed.  Record the query.
+/* 
+** This routine is invoked once per CTE by the parser while parsing a 
+** WITH clause. 
 */
-void sqlite3CteAdd(
+With *sqlite3WithAdd(
   Parse *pParse,          /* Parsing context */
+  With *pWith,            /* Existing WITH clause, or NULL */
   Token *pName,           /* Name of the common-table */
-  ExprList *pArgList,     /* Optional column name list for the table */
+  IdList *pArglist,       /* Optional column name list for the table */
   Select *pQuery          /* Query used to initialize the table */
 ){
-  sqlite3ExprListDelete(pParse->db, pArgList);
+  sqlite3IdListDelete(pParse->db, pArglist);
   sqlite3SelectDelete(pParse->db, pQuery);
+  return 0;
 }
 
-/* This routine is invoked at the end of the entire WITH clause.
+/*
+** Free the contents of the With object passed as the second argument.
 */
-void sqlite3CteFinish(Parse *pParse, int isRecursive){
+void sqlite3WithDelete(sqlite3 *db, With *pWith){
   /* TBD */
 }
 #endif /* !defined(SQLITE_OMIT_CTE) */

src/parse.y

@@ -396,7 +396,7 @@ cmd ::= DROP VIEW ifexists(E) fullname(X). {
 
 //////////////////////// The SELECT statement /////////////////////////////////
 //
-cmd ::= with select(X).  {
+cmd ::= select(X).  {
   SelectDest dest = {SRT_Output, 0, 0, 0, 0};
   sqlite3Select(pParse, X, &dest);
   sqlite3ExplainBegin(pParse->pVdbe);
@@ -407,12 +407,16 @@ cmd ::= with select(X).  {
 
 %type select {Select*}
 %destructor select {sqlite3SelectDelete(pParse->db, $$);}
+%type selectnowith {Select*}
+%destructor selectnowith {sqlite3SelectDelete(pParse->db, $$);}
 %type oneselect {Select*}
 %destructor oneselect {sqlite3SelectDelete(pParse->db, $$);}
 
-select(A) ::= oneselect(X).                      {A = X;}
+select(A) ::= with selectnowith(X). {A = X;}
+
+selectnowith(A) ::= oneselect(X).                      {A = X;}
 %ifndef SQLITE_OMIT_COMPOUND_SELECT
-select(A) ::= select(X) multiselect_op(Y) oneselect(Z).  {
+selectnowith(A) ::= selectnowith(X) multiselect_op(Y) oneselect(Z).  {
   if( Z ){
     Z->op = (u8)Y;
     Z->pPrior = X;
@@ -1365,13 +1369,19 @@ anylist ::= anylist ANY.
 
 
 //////////////////////// COMMON TABLE EXPRESSIONS ////////////////////////////
-with ::= .
+%type with {With*}
+%type wqlist {With*}
+%destructor with {sqlite3WithDelete(pParse->db, $$);}
+
+with(A) ::= . {A = 0;}
 %ifndef SQLITE_OMIT_CTE
-with ::= WITH wqlist.              {sqlite3CteFinish(pParse, 0);}
-with ::= WITH RECURSIVE wqlist.    {sqlite3CteFinish(pParse, 1);}
-wqlist ::= with_query.
-wqlist ::= wqlist COMMA with_query.
-with_query ::= nm(X) idxlist_opt(Y) AS LP select(Z) RP. {
-  sqlite3CteAdd(pParse, &X, Y, Z);
+with(A) ::= WITH wqlist(W).              { A = W; }
+with(A) ::= WITH RECURSIVE wqlist(W).    { A = W; }
+
+wqlist(A) ::= nm(X) inscollist_opt(Y) AS LP select(Z) RP. {
+  A = sqlite3WithAdd(pParse, 0, &X, Y, Z);
+}
+wqlist(A) ::= wqlist(W) COMMA nm(X) inscollist_opt(Y) AS LP select(Z) RP. {
+  A = sqlite3WithAdd(pParse, W, &X, Y, Z);
 }
 %endif  SQLITE_OMIT_CTE

src/sqliteInt.h

@@ -760,6 +760,7 @@ typedef struct VTable VTable;
 typedef struct VtabCtx VtabCtx;
 typedef struct Walker Walker;
 typedef struct WhereInfo WhereInfo;
+typedef struct With With;
 
 /*
 ** Defer sourcing vdbe.h and btree.h until after the "u8" and 
@@ -2631,6 +2632,19 @@ int sqlite3WalkSelectFrom(Walker*, Select*);
 #define WRC_Prune       1   /* Omit children but continue walking siblings */
 #define WRC_Abort       2   /* Abandon the tree walk */
 
+/*
+** An instance of this structure represents a set of CTEs (common table 
+** expressions) created by a single WITH clause.
+*/
+struct With {
+  int nCte;                       /* Number of CTEs */
+  struct Cte {
+    const char *zName;            /* Name of this CTE */
+    IdList *pCol;                 /* List of explicit column names, or NULL */
+    Select *pSelect;              /* The contents of the CTE */
+  } a[1];
+};
+
 /*
 ** Assuming zIn points to the first byte of a UTF-8 character,
 ** advance zIn to point to the first byte of the next UTF-8 character.
@@ -3330,8 +3344,8 @@ const char *sqlite3JournalModename(int);
   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
 #endif
 #ifndef SQLITE_OMIT_CTE
-  void sqlite3CteAdd(Parse*,Token*,ExprList*,Select*);
-  void sqlite3CteFinish(Parse*,int);
+  With *sqlite3WithAdd(Parse*,With*,Token*,IdList*,Select*);
+  void sqlite3WithDelete(sqlite3*,With*);
 #endif
 
 /* Declarations for functions in fkey.c. All of these are replaced by