Earlier detection of a misplaced ORDER BY or LIMIT clause in a compound

SELECT.  This prevents problems in recursive CTEs with multiple recursive
terms in which there is an ORDER BY or LIMIT clause on the last non-recursive
term.

FossilOrigin-Name: e893f88750ea64d45922429e022c585748974016404f2a2b7952f5a227865246

manifest

@@ -1,5 +1,5 @@
-C Fix\sa\scrash\sthat\scould\soccur\sif\sa\ssub-select\sinside\san\sEXISTS\sexpression\sfeatures\san\sORDER\sBY\sclause\scontaining\sone\sor\smore\swindow\sfunctions.
+C Earlier\sdetection\sof\sa\smisplaced\sORDER\sBY\sor\sLIMIT\sclause\sin\sa\scompound\nSELECT.\s\sThis\sprevents\sproblems\sin\srecursive\sCTEs\swith\smultiple\srecursive\nterms\sin\swhich\sthere\sis\san\sORDER\sBY\sor\sLIMIT\sclause\son\sthe\slast\snon-recursive\nterm.
-D 2021-03-04T14:18:22.305
+D 2021-03-04T16:03:32.382
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -531,7 +531,7 @@ F src/os_win.c 77d39873836f1831a9b0b91894fec45ab0e9ca8e067dc8c549e1d1eca1566fe9
 F src/os_win.h 7b073010f1451abe501be30d12f6bc599824944a
 F src/pager.c 970691daea03f9f15e34de671bd8675c1e136232b529e21bfd36d4dba6d41753
 F src/pager.h 4bf9b3213a4b2bebbced5eaa8b219cf25d4a82f385d093cd64b7e93e5285f66f
-F src/parse.y f3e8d7978c10495850c0bb502fe2669b55cf2841c4670b1f7261782e82069471
+F src/parse.y 2107aff88e361bbf8388fdede3fed20fda875f23ba7585ec83b20e3e16a95670
 F src/pcache.c 385ff064bca69789d199a98e2169445dc16e4291fa807babd61d4890c3b34177
 F src/pcache.h 4f87acd914cef5016fae3030343540d75f5b85a1877eed1a2a19b9f284248586
 F src/pcache1.c 388304fd2d91c39591080b5e0f3c62cfba87db20370e7e0554062bfb29740e9f
@@ -542,12 +542,12 @@ F src/printf.c 2b03a80d7c11bb422115dca175a18bf430e9c9dbaa0eee63b758f0c022f8f34f
 F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
 F src/resolve.c 889469e6980181ce77ee8ab3fc84bd52ed6c1c3577fd102d52623d66cc65a3d0
 F src/rowset.c ba9515a922af32abe1f7d39406b9d35730ed65efab9443dc5702693b60854c92
-F src/select.c 1a7931e67fea84f5cb5432c14a334deac72c6a9b25f351607d56bef163707773
+F src/select.c ec87ae50ab868872aca4c92abd9ed9bd0f5f5c76ceb95b66de32d4012f1b255b
 F src/shell.c.in 844417f84df1f6c4fce1c815629a888cfdcf219e86513e9c332bbcc38832f477
 F src/sqlite.h.in 8855a19f37ade8dad189a9e48233a2ebe1b46faf469c7eb0906a654e252dcc57
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 61b38c073d5e1e96a3d45271b257aef27d0d13da2bea5347692ae579475cd95e
-F src/sqliteInt.h 11b9d47e9b9520b123bc75254da7a4e215463e811e62b89518fc5e9a192a0222
+F src/sqliteInt.h 7c4679b3b068149f497fe50203a4b04be6b17b8aba581cdbc75da45329cad915
 F src/sqliteLimit.h d7323ffea5208c6af2734574bae933ca8ed2ab728083caa117c9738581a31657
 F src/status.c 4b8bc2a6905163a38b739854a35b826c737333fab5b1f8e03fa7eb9a4799c4c1
 F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1
@@ -1908,7 +1908,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 4da40620ac8557aba6e1e06e720418b55e9950f406288b03749ef1b117041cd9
+P 9768e7db624fbfe688d61ac06bffca14a169d439d8f65f5a14529af5660d3d2e
-R dbbe9c3309db800b2bcddd55fa5a9e76
+R b7b7ec94c5553295fe0ea94425307f6e
-U dan
+U drh
-Z bd8c7ff2ba0ee91419f8449d3502d963
+Z 0c82ce08ac9825cd2a29c91b8daceab1

manifest.uuid

@@ -1 +1 @@
-9768e7db624fbfe688d61ac06bffca14a169d439d8f65f5a14529af5660d3d2e
+e893f88750ea64d45922429e022c585748974016404f2a2b7952f5a227865246

src/parse.y

@@ -497,11 +497,21 @@ cmd ::= select(X).  {
   static void parserDoubleLinkSelect(Parse *pParse, Select *p){
     assert( p!=0 );
     if( p->pPrior ){
-      Select *pNext = 0, *pLoop;
+      Select *pNext = 0, *pLoop = p;
-      int mxSelect, cnt = 0;
+      int mxSelect, cnt = 1;
-      for(pLoop=p; pLoop; pNext=pLoop, pLoop=pLoop->pPrior, cnt++){
+      while(1){
         pLoop->pNext = pNext;
         pLoop->selFlags |= SF_Compound;
+        pNext = pLoop;
+        pLoop = pLoop->pPrior;
+        if( pLoop==0 ) break;
+        cnt++;        
+        if( pLoop->pOrderBy || pLoop->pLimit ){
+          sqlite3ErrorMsg(pParse,"%s clause should come after %s not before",
+             pLoop->pOrderBy!=0 ? "ORDER BY" : "LIMIT",
+             sqlite3SelectOpName(pNext->op));
+          break;
+        }
       }
       if( (p->selFlags & SF_MultiValue)==0 && 
         (mxSelect = pParse->db->aLimit[SQLITE_LIMIT_COMPOUND_SELECT])>0 &&

src/select.c

@@ -1390,7 +1390,7 @@ KeyInfo *sqlite3KeyInfoFromExprList(
 /*
 ** Name of the connection operator, used for error messages.
 */
-static const char *selectOpName(int id){
+const char *sqlite3SelectOpName(int id){
   char *z;
   switch( id ){
     case TK_ALL:       z = "UNION ALL";   break;
@@ -2609,12 +2609,8 @@ static int multiSelect(
   db = pParse->db;
   pPrior = p->pPrior;
   dest = *pDest;
-  if( pPrior->pOrderBy || pPrior->pLimit ){
+  assert( pPrior->pOrderBy==0 );
-    sqlite3ErrorMsg(pParse,"%s clause should come after %s not before",
+  assert( pPrior->pLimit==0 );
-      pPrior->pOrderBy!=0 ? "ORDER BY" : "LIMIT", selectOpName(p->op));
-    rc = 1;
-    goto multi_select_end;
-  }
 
   v = sqlite3GetVdbe(pParse);
   assert( v!=0 );  /* The VDBE already created by calling function */
@@ -2757,7 +2753,7 @@ static int multiSelect(
         p->pLimit = 0;
         uniondest.eDest = op;
         ExplainQueryPlan((pParse, 1, "%s USING TEMP B-TREE",
-                          selectOpName(p->op)));
+                          sqlite3SelectOpName(p->op)));
         rc = sqlite3Select(pParse, p, &uniondest);
         testcase( rc!=SQLITE_OK );
         assert( p->pOrderBy==0 );
@@ -2833,7 +2829,7 @@ static int multiSelect(
         p->pLimit = 0;
         intersectdest.iSDParm = tab2;
         ExplainQueryPlan((pParse, 1, "%s USING TEMP B-TREE",
-                          selectOpName(p->op)));
+                          sqlite3SelectOpName(p->op)));
         rc = sqlite3Select(pParse, p, &intersectdest);
         testcase( rc!=SQLITE_OK );
         pDelete = p->pPrior;
@@ -2942,7 +2938,8 @@ void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p){
     sqlite3ErrorMsg(pParse, "all VALUES must have the same number of terms");
   }else{
     sqlite3ErrorMsg(pParse, "SELECTs to the left and right of %s"
-      " do not have the same number of result columns", selectOpName(p->op));
+      " do not have the same number of result columns",
+      sqlite3SelectOpName(p->op));
   }
 }
 
@@ -3334,7 +3331,7 @@ static int multiSelectOrderBy(
   sqlite3SelectDestInit(&destA, SRT_Coroutine, regAddrA);
   sqlite3SelectDestInit(&destB, SRT_Coroutine, regAddrB);
 
-  ExplainQueryPlan((pParse, 1, "MERGE (%s)", selectOpName(p->op)));
+  ExplainQueryPlan((pParse, 1, "MERGE (%s)", sqlite3SelectOpName(p->op)));
 
   /* Generate a coroutine to evaluate the SELECT statement to the
   ** left of the compound operator - the "A" select.

src/sqliteInt.h

@@ -4795,6 +4795,7 @@ void sqlite3KeyInfoUnref(KeyInfo*);
 KeyInfo *sqlite3KeyInfoRef(KeyInfo*);
 KeyInfo *sqlite3KeyInfoOfIndex(Parse*, Index*);
 KeyInfo *sqlite3KeyInfoFromExprList(Parse*, ExprList*, int, int);
+const char *sqlite3SelectOpName(int);
 int sqlite3HasExplicitNulls(Parse*, ExprList*);
 
 #ifdef SQLITE_DEBUG