A few bits and bobs of code generation toward getting RIGHT JOIN to work.

Much more remains to do.

FossilOrigin-Name: 55b4543122646997d928598343bc467c993f971e86e9037c85430cc948750576

manifest

@@ -1,5 +1,5 @@
-C Merge\sthe\ssqlite3WhereMalloc()\sroutine\sfrom\strunk\sinto\sthe\sright-join\sbranch.
+C A\sfew\sbits\sand\sbobs\sof\scode\sgeneration\stoward\sgetting\sRIGHT\sJOIN\sto\swork.\nMuch\smore\sremains\sto\sdo.
-D 2022-04-09T03:12:52.801
+D 2022-04-09T03:16:26.838
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -639,9 +639,9 @@ F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
 F src/wal.c b9df133a705093da8977da5eb202eaadb844839f1c7297c08d33471f5491843d
 F src/wal.h c3aa7825bfa2fe0d85bef2db94655f99870a285778baa36307c0a16da32b226a
 F src/walker.c f890a3298418d7cba3b69b8803594fdc484ea241206a8dfa99db6dd36f8cbb3b
-F src/where.c 20b6907d66577c02bc2be434c3c8fd5f00f0112d467cb8ae5d97ced3af14f484
+F src/where.c 3bd028fa90533d5caad6c3160e404eff2595ee751a8e2c1f4d1617975caa192c
-F src/whereInt.h 41ce0a8c0368372d8422e420e05a1e037624ce52fae139c3c19538ee491fb4c0
+F src/whereInt.h 5cd48fd01bff983a86d0ef02f8e0c9a5c870dbaebc4d7b2ae2212aefd5df9cd7
-F src/wherecode.c 79813939e009cbd8a042d57e6c0cad1a437d8e2e19b8be61c70760089f055c89
+F src/wherecode.c f25a1d1ad2a8d002805e107d2ec323db410ad0246a52b944d10b8d4da0e01f7c
 F src/whereexpr.c ac8985bbd983f34273b1e0d05cd738ff436331674c1b22f4caf6537e1eca4691
 F src/window.c 42a71595263dbd8ef8248218e4fc7d4b5ddccece52146ad48e079342d93f6f8f
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
@@ -1945,8 +1945,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 415abd6731b8e8a605adabfa6066c8a852a8531c300df41325d5f7e75cae5a70 f237e1d8cc41b937f34288daebfacf5f7b0990a807a805e0cb6b45bc730192d6
+P b1b3845aa38f469a27f07c8f6e8a98334f7967b19661ee4cf155d6997afd9d4c
-R 14570ffbcb3ed6fd5a47242c31653712
+R bc7d39cae3cf9a210e7fffa29f471f8f
 U drh
-Z 80db52d601f5cc05776abad4ced7d9c5
+Z cd50394e42c6a1bed1272dd9e082a119
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-b1b3845aa38f469a27f07c8f6e8a98334f7967b19661ee4cf155d6997afd9d4c
+55b4543122646997d928598343bc467c993f971e86e9037c85430cc948750576

src/where.c

@@ -5870,8 +5870,22 @@ WhereInfo *sqlite3WhereBegin(
     }
     if( iDb>=0 ) sqlite3CodeVerifySchema(pParse, iDb);
     if( pTabItem->fg.jointype & JT_RIGHT ){
-      VdbeModuleComment((v, "TO-DO: Setup for the RIGHT JOIN of %s",
+      assert( pTab==pTabItem->pTab );
-                         pTab->zName));
+      pLevel->iRJMatch = pParse->nTab++;
+      if( HasRowid(pTab) ){
+        KeyInfo *pInfo;
+        sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pLevel->iRJMatch, 1);
+        pInfo = sqlite3KeyInfoAlloc(pParse->db, 1, 0);
+        if( pInfo ){
+          pInfo->aColl[0] = 0;
+          pInfo->aSortFlags[0] = 0;
+          sqlite3VdbeAppendP4(v, pInfo, P4_KEYINFO);
+        }
+      }else{
+        Index *pPk = sqlite3PrimaryKeyIndex(pTab);
+        sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pLevel->iRJMatch, pPk->nKeyCol);
+        sqlite3VdbeSetP4KeyInfo(pParse, pPk);
+      }
     }
   }
   pWInfo->iTop = sqlite3VdbeCurrentAddr(v);

src/whereInt.h

@@ -75,6 +75,7 @@ struct WhereLevel {
   int addrLikeRep;      /* LIKE range processing address */
 #endif
   int regFilter;        /* Bloom filter */
+  int iRJMatch;         /* Cursor or rowset used for matched RIGHT JOIN rows */
   u8 iFrom;             /* Which entry in the FROM clause */
   u8 op, p3, p5;        /* Opcode, P3 & P5 of the opcode that ends the loop */
   int p1, p2;           /* Operands of the opcode used to end the loop */

src/wherecode.c

@@ -2721,6 +2721,41 @@ Bitmask sqlite3WhereCodeOneLoopStart(
     }
   }
 
+  /* For a RIGHT OUTER JOIN, record the fact that the current row has
+  ** been matched at least once.
+  */
+  if( pLevel->iRJMatch ){
+    Table *pTab;
+    int nPk;
+    int r;
+    int jmp1 = 0;
+
+    pTab = pWInfo->pTabList->a[pLevel->iFrom].pTab;
+    if( HasRowid(pTab) ){
+      r = sqlite3GetTempRange(pParse, 2);
+      sqlite3ExprCodeGetColumnOfTable(v, pTab, pLevel->iTabCur, -1, r+1);
+      nPk = 1;
+    }else{
+      int iPk;
+      Index *pPk = sqlite3PrimaryKeyIndex(pTab);
+      nPk = pPk->nKeyCol;
+      r = sqlite3GetTempRange(pParse, nPk+1);
+      for(iPk=0; iPk<nPk; iPk++){
+        int iCol = pPk->aiColumn[iPk];
+        sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, iCol,r+1+iPk);
+      }
+    }
+    jmp1 = sqlite3VdbeAddOp4Int(v, OP_Found, pLevel->iRJMatch, 0, r+1, nPk);
+    VdbeCoverage(v);
+    sqlite3VdbeAddOp3(v, OP_MakeRecord, r+1, nPk, r);
+    sqlite3VdbeAddOp4Int(v, OP_IdxInsert, pLevel->iRJMatch, r, r+1, nPk);
+    sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
+    sqlite3VdbeJumpHere(v, jmp1);
+
+    /* Release the array of temp registers */
+    sqlite3ReleaseTempRange(pParse, r, nPk+1);
+  }
+
 #if WHERETRACE_ENABLED /* 0x20800 */
   if( sqlite3WhereTrace & 0x20000 ){
     sqlite3DebugPrintf("All WHERE-clause terms after coding level %d:\n",