Further simplifications of the code for the LIMIT clause on an UPDATE or DELETE....

FossilOrigin-Name: 282c6a46b25f4e4278fd4c8b0b1cde1de28d8f51

diff --git a/manifest b/manifest
index d0066e8ed9a7b31b7c897dc444bf900ebcd22a67..c053be0c7cb1da1c5bd72f447fd66f482b6a4ef1 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Add\sthe\sgenfkey\sprogram\sto\sthe\stool/\sdirectory.\s(CVS\s5796)
-D 2008-10-10T17:58:27
+C Further\ssimplifications\sof\sthe\scode\sfor\sthe\sLIMIT\sclause\son\san\sUPDATE\sor\sDELETE.\s\sAdded\sa\sfew\stest\scases\sto\swherelimit.test.\s(CVS\s5797)
+D 2008-10-10T18:25:46
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in 7fc26e087207e7a4a7723583dbd7997477af3b13
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -106,7 +106,7 @@ F src/build.c 8714bd809583bbe07bf22d0e1808a3fc31abe330
 F src/callback.c e970e5beddbdb23f89a6d05cb1a6419d9f755624
 F src/complete.c cb14e06dbe79dee031031f0d9e686ff306afe07c
 F src/date.c 1b1fc801df40aae891bff8b03f65313df192d677
-F src/delete.c f72c98c5770c94f1a8b7bbdf7aeb49503a4927a4
+F src/delete.c c7aaf47f274494f9ae1f89cf095ca890b1d9d2bf
 F src/expr.c 0ceafeff3a4e0f460d6a7695a675ae12391e313d
 F src/fault.c dc88c821842157460750d2d61a8a8b4197d047ff
 F src/func.c 8431b40a7843d1024145684d303c55b4ee087bbe
@@ -140,7 +140,7 @@ F src/os_unix.c f33b69d8a85372b270fe37ee664a4c2140a5217d
 F src/os_win.c 04033a86a39f49cb8e348f515eb0116aa9d36678
 F src/pager.c d98f56128e849083f2f612196efebd982c491fea
 F src/pager.h 9c1917be28fff58118e1fe0ddbc7adfb8dd4f44d
-F src/parse.y 8862ab3391c9546f25d0e929906f100d0a9e7d2b
+F src/parse.y e8620c7efd46659fd7a9cbad13b51225af7f600c
 F src/pcache.c f8d7beceba164a34441ac37e88abb3a404f968a7
 F src/pcache.h 28d9ce2d66909db1f01652586450b62b64793093
 F src/pragma.c f0f48d0d50e9d8fa785178fc2410244c06f6a287
@@ -152,7 +152,7 @@ F src/select.c d910d7350df0d918e22286c5bfd39d4ea68ec813
 F src/shell.c d83b578a8ccdd3e0e7fef4388a0887ce9f810967
 F src/sqlite.h.in 28e6466da6b90e56bfbc6c50a1a281931a8c733c
 F src/sqlite3ext.h 1e3887c9bd3ae66cb599e922824b04cd0d0f2c3e
-F src/sqliteInt.h 0da9c664d89995d28587548048837e3063fa0be3
+F src/sqliteInt.h f60fac64c8970ca366080daa3aa65b9a54a2334a
 F src/sqliteLimit.h f435e728c6b620ef7312814d660a81f9356eb5c8
 F src/status.c 237b193efae0cf6ac3f0817a208de6c6c6ef6d76
 F src/table.c 22744786199c9195720c15a7a42cb97b2e2728d8
@@ -618,7 +618,7 @@ F test/where3.test 97d3936e6a443b968f1a61cdcc0f673252000e94
 F test/where4.test e9b9e2f2f98f00379e6031db6a6fca29bae782a2
 F test/where5.test fdf66f96d29a064b63eb543e28da4dfdccd81ad2
 F test/where6.test 42c4373595f4409d9c6a9987b4a60000ad664faf
-F test/wherelimit.test 3464395714151cdce9f7f28a19d2cf344bd934c8
+F test/wherelimit.test 5e9fd41e79bb2b2d588ed999d641d9c965619b31
 F test/zeroblob.test 792124852ec61458a2eb527b5091791215e0be95
 F tool/diffdb.c 7524b1b5df217c20cd0431f6789851a4e0cb191b
 F tool/fragck.tcl 5265a95126abcf6ab357f7efa544787e5963f439
@@ -648,7 +648,7 @@ F tool/speedtest16.c c8a9c793df96db7e4933f0852abb7a03d48f2e81
 F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
-P 3bb33cf59da49f13201c0226e964cda067a4e780
-R aef0f958c65788fc079e6ee823734d14
-U danielk1977
-Z 3eb8c7cc05cdf3fbc1c3afcf6ba604ca
+P 84e73fe8a6f538c4b1bb4f641a661d6fafb60c76
+R eb4c22bf5cef8091ed9bce14d73bbe63
+U shane
+Z 9ca81fedb812b2854e888eab6c64b7ec

diff --git a/manifest.uuid b/manifest.uuid
index e5584ad8d4c0491134e364582b486fc7364a5b66..2d6ec05808572e1ad16a264e3703f9cc358b0a66 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-84e73fe8a6f538c4b1bb4f641a661d6fafb60c76
\ No newline at end of file
+282c6a46b25f4e4278fd4c8b0b1cde1de28d8f51
\ No newline at end of file

diff --git a/src/delete.c b/src/delete.c
index 82cc1336c0d4f0c349c46efa7210b3b78b9cf434..7f98812a6cbe03e4cf7a88c4a9c3d61e9588c847 100644 (file)
--- a/src/delete.c
+++ b/src/delete.c
@@ -12,7 +12,7 @@
 ** This file contains C code routines that are called by the parser
 ** in order to generate code for DELETE FROM statements.
 **
-** $Id: delete.c,v 1.180 2008/10/10 13:35:58 shane Exp $
+** $Id: delete.c,v 1.181 2008/10/10 18:25:46 shane Exp $
 */
 #include "sqliteInt.h"
 
@@ -126,24 +126,37 @@ void sqlite3MaterializeView(
 **                               pLimitWhere (pInClause)
 */
 Expr *sqlite3LimitWhere(
-  Parse *pParse,          /* The parser context */
-  SrcList *pSrc,          /* the FROM clause -- which tables to scan */
-  Expr *pWhere,           /* The WHERE clause.  May be null */
-  ExprList *pOrderBy,     /* The ORDER BY clause.  May be null */
-  Expr *pLimit,           /* The LIMIT clause.  May be null */
-  Expr *pOffset           /* The OFFSET clause.  May be null */
+  Parse *pParse,               /* The parser context */
+  SrcList *pSrc,               /* the FROM clause -- which tables to scan */
+  Expr *pWhere,                /* The WHERE clause.  May be null */
+  ExprList *pOrderBy,          /* The ORDER BY clause.  May be null */
+  Expr *pLimit,                /* The LIMIT clause.  May be null */
+  Expr *pOffset,               /* The OFFSET clause.  May be null */
+  char *zStmtType              /* Either DELETE or UPDATE.  For error messages. */
 ){
-  Expr *pWhereRowid = NULL;
-  Expr *pInClause = NULL;
-  Expr *pSelectRowid = NULL;
-  ExprList *pEList = NULL;
-  SrcList *pSelectSrc = NULL;
-  Select *pSelect = NULL;
+  Expr *pWhereRowid = NULL;    /* WHERE rowid .. */
+  Expr *pInClause = NULL;      /* WHERE rowid IN ( select ) */
+  Expr *pSelectRowid = NULL;   /* SELECT rowid ... */
+  ExprList *pEList = NULL;     /* Expression list contaning only pSelectRowid */
+  SrcList *pSelectSrc = NULL;  /* SELECT rowid FROM x ... (dup of pSrc) */
+  Select *pSelect = NULL;      /* Complete SELECT tree */
+
+  /* Check that there isn't an ORDER BY without a LIMIT clause.
+  */
+  if( pOrderBy && (pLimit == 0) ) {
+    sqlite3ErrorMsg(pParse, "ORDER BY without LIMIT on %s", zStmtType);
+    pParse->parseError = 1;
+    goto limit_where_cleanup_2;
+  }
 
   /* We only need to generate a select expression if there
   ** is a limit/offset term to enforce.
   */
-  if (!pLimit && !pOffset) return pWhere;
+  if( pLimit == 0 ) {
+    /* if pLimit is null, pOffset will always be null as well. */
+    assert( pOffset == 0 );
+    return pWhere;
+  }
 
   /* Generate a select expression tree to enforce the limit/offset 
   ** term for the DELETE or UPDATE statement.  For example:
@@ -155,35 +168,43 @@ Expr *sqlite3LimitWhere(
   */
 
   pSelectRowid = sqlite3Expr(pParse->db, TK_ROW, 0, 0, 0);
-  if( pSelectRowid == 0 ) return 0;
+  if( pSelectRowid == 0 ) goto limit_where_cleanup_2;
   pEList = sqlite3ExprListAppend(pParse, 0, pSelectRowid, 0);
-  if( pEList == 0 ) return 0;
+  if( pEList == 0 ) goto limit_where_cleanup_2;
 
   /* duplicate the FROM clause as it is needed by both the DELETE/UPDATE tree
   ** and the SELECT subtree. */
   pSelectSrc = sqlite3SrcListDup(pParse->db, pSrc);
   if( pSelectSrc == 0 ) {
     sqlite3ExprListDelete(pParse->db, pEList);
-    return 0;
+    goto limit_where_cleanup_2;
   }
 
   /* generate the SELECT expression tree. */
   pSelect = sqlite3SelectNew(pParse,pEList,pSelectSrc,pWhere,0,0,pOrderBy,0,pLimit,pOffset);
   if( pSelect == 0 ) return 0;
 
+  /* now generate the new WHERE rowid IN clause for the DELETE/UDPATE */
   pWhereRowid = sqlite3Expr(pParse->db, TK_ROW, 0, 0, 0);
-  if( pWhereRowid == 0 ) goto limit_where_cleanup;
+  if( pWhereRowid == 0 ) goto limit_where_cleanup_1;
   pInClause = sqlite3PExpr(pParse, TK_IN, pWhereRowid, 0, 0);
-  if( pInClause == 0 ) goto limit_where_cleanup;
+  if( pInClause == 0 ) goto limit_where_cleanup_1;
 
   pInClause->pSelect = pSelect;
   sqlite3ExprSetHeight(pParse, pInClause);
   return pInClause;
 
   /* something went wrong. clean up anything allocated. */
-limit_where_cleanup:
+limit_where_cleanup_1:
   sqlite3SelectDelete(pParse->db, pSelect);
   return 0;
+
+limit_where_cleanup_2:
+  sqlite3ExprDelete(pParse->db, pWhere);
+  sqlite3ExprListDelete(pParse->db, pOrderBy);
+  sqlite3ExprDelete(pParse->db, pLimit);
+  sqlite3ExprDelete(pParse->db, pOffset);
+  return 0;
 }
 #endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY) */
 

diff --git a/src/parse.y b/src/parse.y
index 61b322fa465eac43335d1da0ac268250482eb485..3959269ccfaa35582609de4084e12a4099a11498 100644 (file)
--- a/src/parse.y
+++ b/src/parse.y
@@ -14,7 +14,7 @@
 ** the parser.  Lemon will also generate a header file containing
 ** numeric codes for all of the tokens.
 **
-** @(#) $Id: parse.y,v 1.258 2008/10/10 17:47:21 danielk1977 Exp $
+** @(#) $Id: parse.y,v 1.259 2008/10/10 18:25:46 shane Exp $
 */
 
 // All token codes are small integers with #defines that begin with "TK_"
@@ -582,13 +582,8 @@ limit_opt(A) ::= LIMIT expr(X) COMMA expr(Y).
 cmd ::= DELETE FROM fullname(X) indexed_opt(I) where_opt(W) 
         orderby_opt(O) limit_opt(L). {
   sqlite3SrcListIndexedBy(pParse, X, &I);
-  if( O && !L.pLimit ){
-    sqlite3ErrorMsg(pParse, "ORDER BY without LIMIT on DELETE");
-    pParse->parseError = 1;
-  }else{
-    W = sqlite3LimitWhere(pParse, X, W, O, L.pLimit, L.pOffset);
-    sqlite3DeleteFrom(pParse,X,W);
-  }
+  W = sqlite3LimitWhere(pParse, X, W, O, L.pLimit, L.pOffset, "DELETE");
+  sqlite3DeleteFrom(pParse,X,W);
 }
 %endif
 %ifndef SQLITE_ENABLE_UPDATE_DELETE_LIMIT
@@ -610,13 +605,8 @@ where_opt(A) ::= WHERE expr(X).       {A = X;}
 cmd ::= UPDATE orconf(R) fullname(X) indexed_opt(I) SET setlist(Y) where_opt(W) orderby_opt(O) limit_opt(L).  {
   sqlite3SrcListIndexedBy(pParse, X, &I);
   sqlite3ExprListCheckLength(pParse,Y,"set list"); 
-  if( O && !L.pLimit ){
-    sqlite3ErrorMsg(pParse, "ORDER BY without LIMIT on UPDATE");
-    pParse->parseError = 1;
-  }else{
-    W = sqlite3LimitWhere(pParse, X, W, O, L.pLimit,L.pOffset);
-    sqlite3Update(pParse,X,Y,W,R);
-  }
+  W = sqlite3LimitWhere(pParse, X, W, O, L.pLimit, L.pOffset, "UPDATE");
+  sqlite3Update(pParse,X,Y,W,R);
 }
 %endif
 %ifndef SQLITE_ENABLE_UPDATE_DELETE_LIMIT

diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index f13a739db76f63a06bec69c34542044f96d18e1b..caf62320b1e8d8b96ba20a5a2161f4113c12c0c9 100644 (file)
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -11,7 +11,7 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.780 2008/10/10 04:34:16 shane Exp $
+** @(#) $Id: sqliteInt.h,v 1.781 2008/10/10 18:25:46 shane Exp $
 */
 #ifndef _SQLITEINT_H_
 #define _SQLITEINT_H_
@@ -2162,7 +2162,7 @@ Table *sqlite3SrcListLookup(Parse*, SrcList*);
 int sqlite3IsReadOnly(Parse*, Table*, int);
 void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
-Expr *sqlite3LimitWhere(Parse *, SrcList *, Expr *, ExprList *, Expr *, Expr *);
+Expr *sqlite3LimitWhere(Parse *, SrcList *, Expr *, ExprList *, Expr *, Expr *, char *);
 #endif
 void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
 void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);

diff --git a/test/wherelimit.test b/test/wherelimit.test
index 5352d6fcdc6475995cb6d353a931aa4fbb606fb6..f0cfbb61e85eac1b8276dfd74b193e3b97f26717 100644 (file)
--- a/test/wherelimit.test
+++ b/test/wherelimit.test
@@ -12,7 +12,7 @@
 # focus of this file is testing the LIMIT ... OFFSET ... clause
 #  of UPDATE and DELETE statements.
 #
-# $Id: wherelimit.test,v 1.1 2008/10/10 06:02:00 shane Exp $
+# $Id: wherelimit.test,v 1.2 2008/10/10 18:25:46 shane Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -57,6 +57,15 @@ ifcapable {update_delete_limit} {
     catchsql {UPDATE t1 AS a SET y=1 WHERE x=1}
   } {1 {near "AS": syntax error}}
 
+  # OFFSET w/o LIMIT
+  do_test wherelimit-0.6 {
+    catchsql {DELETE FROM t1 WHERE x=1 OFFSET 2}
+  } {1 {near "OFFSET": syntax error}}
+  do_test wherelimit-0.7 {
+    catchsql {UPDATE t1 SET y=1 WHERE x=1 OFFSET 2}
+  } {1 {near "OFFSET": syntax error}}
+
+
   # check deletes w/o where clauses but with limit/offsets
   create_test_data 5
   do_test wherelimit-1.0 {