SQLite

  Index *pUpIdx = 0;   /* Index to which to apply the upsert */
  u8 isUpdate;         /* True if this is an UPDATE operation */
  u8 bAffinityDone = 0;  /* True if the OP_Affinity operation has been run */
  int upsertBypass = 0;  /* Address of Goto to bypass upsert subroutine */
  int upsertJump = 0;    /* Address of Goto that jumps into upsert subroutine */
  int ipkTop = 0;        /* Top of the IPK uniqueness check */
  int ipkBottom = 0;     /* OP_Goto at the end of the IPK uniqueness check */
  /* Variables associated with retesting uniqueness constraints after
  ** replace triggers fire have run */
  int regTrigCnt;       /* Register used to count replace trigger invocations */
  int addrRecheck = 0;  /* Jump here to recheck all uniqueness constraints */
  int lblRecheckOk = 0; /* Each recheck jumps to this label if it passes */
  Trigger *pTrigger;    /* List of DELETE triggers on the table pTab */
  int nReplaceTrig = 0; /* Number of replace triggers coded */

  isUpdate = regOldData!=0;
  db = pParse->db;
  v = sqlite3GetVdbe(pParse);
  assert( v!=0 );
  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
  nCol = pTab->nCol;

    }else if( (pUpIdx = pUpsert->pUpsertIdx)!=0 ){
      /* If the constraint-target uniqueness check must be run first.
      ** Jump to that uniqueness check now */
      upsertJump = sqlite3VdbeAddOp0(v, OP_Goto);
      VdbeComment((v, "UPSERT constraint goes first"));
    }
  }

  /* Determine if it is possible that triggers (either explicitly coded
  ** triggers or FK resolution actions) might run as a result of deletes
  ** that happen when OE_Replace conflict resolution occurs. (Call these
  ** "replace triggers".)  If any replace triggers run, we will need to
  ** recheck all of the uniqueness constraints after they have all run.
  ** But on the recheck, the resolution is OE_Abort instead of OE_Replace.
  **
  ** If replace triggers are a possibility, then
  **
  **   (1) Allocate register regTrigCnt and initialize it to zero.
  **       That register will count the number of replace triggers that
  **       fire.  Constraint recheck only occurs if the number if positive.
  **   (2) Initialize pTrigger to the set of all DELETE triggers.
  **   (3) Initialize addrRecheck and lblRecheckOk
  **
  ** The uniqueness rechecking code will create a series of tests to run
  ** in a second pass.  The addrRecheck and lblRecheckOk variables are
  ** used to link together these tests which are separated from each other
  ** in the generate bytecode.
  */
  if( (db->flags & (SQLITE_RecTriggers|SQLITE_ForeignKeys))==0 ){
    /* There are not DELETE triggers nor FK constraints.  No constraint
    ** rechecks are needed. */
    pTrigger = 0;
    regTrigCnt = 0;
  }else{
    if( db->flags&SQLITE_RecTriggers ){
      pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
      regTrigCnt = pTrigger!=0 || sqlite3FkRequired(pParse, pTab, 0, 0);
    }else{
      pTrigger = 0;
      regTrigCnt = sqlite3FkRequired(pParse, pTab, 0, 0);
    }
    if( regTrigCnt ){
      /* Replace triggers might exist.  Allocate the counter and
      ** initialize it to zero. */
      regTrigCnt = ++pParse->nMem;
      sqlite3VdbeAddOp2(v, OP_Integer, 0, regTrigCnt);
      VdbeComment((v, "trigger count"));
      lblRecheckOk = sqlite3VdbeMakeLabel(pParse);
      addrRecheck = lblRecheckOk;
    }
  }

  /* If rowid is changing, make sure the new rowid does not previously
  ** exist in the table.
  */
  if( pkChng && pPk==0 ){
    int addrRowidOk = sqlite3VdbeMakeLabel(pParse);

        ** but being more selective here allows statements like:
        **
        **   REPLACE INTO t(rowid) VALUES($newrowid)
        **
        ** to run without a statement journal if there are no indexes on the
        ** table.
        */
        if( regTrigCnt ){




          sqlite3MultiWrite(pParse);
          sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
                                   regNewData, 1, 0, OE_Replace, 1, -1);
          sqlite3VdbeAddOp2(v, OP_AddImm, regTrigCnt, 1); /* incr trigger cnt */
          nReplaceTrig++;

        }else{
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
          assert( HasRowid(pTab) );
          /* This OP_Delete opcode fires the pre-update-hook only. It does
          ** not modify the b-tree. It is more efficient to let the coming
          ** OP_Insert replace the existing entry than it is to delete the
          ** existing entry and then insert a new one. */

  ** WITHOUT ROWID table.
  */
  for(ix=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, ix++){
    int regIdx;          /* Range of registers hold conent for pIdx */
    int regR;            /* Range of registers holding conflicting PK */
    int iThisCur;        /* Cursor for this UNIQUE index */
    int addrUniqueOk;    /* Jump here if the UNIQUE constraint is satisfied */
    int addrConflictCk;  /* First opcode in the conflict check logic */

    if( aRegIdx[ix]==0 ) continue;  /* Skip indices that do not change */
    if( pUpIdx==pIdx ){
      addrUniqueOk = upsertJump+1;
      upsertBypass = sqlite3VdbeGoto(v, 0);
      VdbeComment((v, "Skip upsert subroutine"));
      sqlite3VdbeJumpHere(v, upsertJump);

      sqlite3VdbeResolveLabel(v, addrUniqueOk);
      continue;
    }
#endif /* ifndef SQLITE_ENABLE_PREUPDATE_HOOK */

    /* Check to see if the new index entry will be unique */
    sqlite3VdbeVerifyAbortable(v, onError);
    addrConflictCk = 
      sqlite3VdbeAddOp4Int(v, OP_NoConflict, iThisCur, addrUniqueOk,
                           regIdx, pIdx->nKeyCol); VdbeCoverage(v);

    /* Generate code to handle collisions */
    regR = (pIdx==pPk) ? regIdx : sqlite3GetTempRange(pParse, nPkField);
    if( isUpdate || onError==OE_Replace ){
      if( HasRowid(pTab) ){
        sqlite3VdbeAddOp2(v, OP_IdxRowid, iThisCur, regR);
        /* Conflict only if the rowid of the existing index entry

#endif
      case OE_Ignore: {
        testcase( onError==OE_Ignore );
        sqlite3VdbeGoto(v, ignoreDest);
        break;
      }
      default: {
        int nConflictCk;   /* Number of opcodes in conflict check logic */

        assert( onError==OE_Replace );

        nConflictCk = sqlite3VdbeCurrentAddr(v) - addrConflictCk;

        if( regTrigCnt ){
          sqlite3MultiWrite(pParse);
          nReplaceTrig++;
        }
        sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
            regR, nPkField, 0, OE_Replace,
            (pIdx==pPk ? ONEPASS_SINGLE : ONEPASS_OFF), iThisCur);
        if( regTrigCnt ){
          VdbeOp *pOp;     /* Conflict check opcode to copy */
          int p2;          /* New P2 value for copied conflict check opcode */
          int addrBypass;  /* Jump destination to bypass recheck logic */

          sqlite3VdbeAddOp2(v, OP_AddImm, regTrigCnt, 1); /* incr trigger cnt */
          addrBypass = sqlite3VdbeAddOp0(v, OP_Goto);  /* Bypass recheck */
          VdbeComment((v, "bypass recheck"));

          /* Here we insert code that will be invoked after all constraint
          ** checks have run, if and only if one or more replace triggers
          ** fired. */
          sqlite3VdbeResolveLabel(v, lblRecheckOk);
          lblRecheckOk = sqlite3VdbeMakeLabel(pParse);
          if( pIdx->pPartIdxWhere ){
            /* Bypass the recheck if this partial index is not defined
            ** for the current row */
            sqlite3VdbeAddOp2(v, OP_IsNull, regIdx, lblRecheckOk);
            VdbeCoverage(v);
          }
          /* Copy the constraint check code from above, except change
          ** the constraint-ok jump destination to be the address of
          ** the next retest block */
          pOp = sqlite3VdbeGetOp(v, addrConflictCk);
          while( nConflictCk>0 && !db->mallocFailed ){
            if( sqlite3OpcodeProperty[pOp->opcode]&OPFLG_JUMP ){
              p2 = lblRecheckOk;
            }else{
              p2 = pOp->p2;
            }
            if( pOp->opcode!=OP_IdxRowid ){
              sqlite3VdbeAddOp4(v, pOp->opcode, pOp->p1, p2, pOp->p3,
                                pOp->p4.z, pOp->p4type);
              sqlite3VdbeChangeP5(v, pOp->p5);
            }
            nConflictCk--;
            pOp++;
          }
          /* If the retest fails, issue an abort */
          sqlite3UniqueConstraint(pParse, OE_Abort, pIdx);

          sqlite3VdbeJumpHere(v, addrBypass); /* Terminate the recheck bypass */
        }
        seenReplace = 1;
        break;
      }
    }
    if( pUpIdx==pIdx ){
      sqlite3VdbeGoto(v, upsertJump+1);
      sqlite3VdbeJumpHere(v, upsertBypass);
    }else{
      sqlite3VdbeResolveLabel(v, addrUniqueOk);
    }
    if( regR!=regIdx ) sqlite3ReleaseTempRange(pParse, regR, nPkField);
  }

  /* If the IPK constraint is a REPLACE, run it last */
  if( ipkTop ){
    sqlite3VdbeGoto(v, ipkTop);
    VdbeComment((v, "Do IPK REPLACE"));
    sqlite3VdbeJumpHere(v, ipkBottom);
  }

  /* Recheck all uniqueness constraints after replace triggers have run */
  testcase( regTrigCnt!=0 && nReplaceTrig==0 );
  if( nReplaceTrig ){
    sqlite3VdbeAddOp2(v, OP_IfNot, regTrigCnt, lblRecheckOk);VdbeCoverage(v);
    if( !pPk ){
      if( isUpdate ){
        sqlite3VdbeAddOp3(v, OP_Eq, regNewData, addrRecheck, regOldData);
        sqlite3VdbeChangeP5(v, SQLITE_NOTNULL);
        VdbeCoverage(v);
      }
      sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, addrRecheck, regNewData);
      VdbeCoverage(v);
      sqlite3RowidConstraint(pParse, OE_Abort, pTab);
    }else{
      sqlite3VdbeGoto(v, addrRecheck);
    }
    sqlite3VdbeResolveLabel(v, lblRecheckOk);
  }

  /* Generate the table record */
  if( HasRowid(pTab) ){
    int regRec = aRegIdx[ix];
    sqlite3VdbeAddOp3(v, OP_MakeRecord, regNewData+1, pTab->nCol, regRec);
    sqlite3SetMakeRecordP5(v, pTab);
    if( !bAffinityDone ){

  END;
  INSERT INTO p1 VALUES(1, 1);
  INSERT INTO c1 VALUES(2, 1);
  REPLACE INTO p1 VALUES(3, 1);
} {1 {UNIQUE constraint failed: p1.b}}
integrity_check insert-16.7

# 2019-10-25 ticket c1e19e12046d23fe
do_catchsql_test insert-17.1 {
  PRAGMA temp.recursive_triggers = true;
  DROP TABLE IF EXISTS t0;
  CREATE TABLE t0(aa, bb);
  CREATE UNIQUE INDEX t0bb ON t0(bb);
  CREATE TRIGGER "r17.1" BEFORE DELETE ON t0
    BEGIN INSERT INTO t0(aa,bb) VALUES(99,1);
  END;
  INSERT INTO t0(aa,bb) VALUES(10,20);
  REPLACE INTO t0(aa,bb) VALUES(30,20);
} {1 {UNIQUE constraint failed: t0.rowid}}
integrity_check insert-17.2
do_catchsql_test insert-17.3 {
  DROP TABLE IF EXISTS t1;
  CREATE TABLE t1(a, b UNIQUE, c UNIQUE);
  INSERT INTO t1(a,b,c) VALUES(1,1,1),(2,2,2),(3,3,3),(4,4,4);
  CREATE TRIGGER "r17.3" AFTER DELETE ON t1 WHEN OLD.c<>3 BEGIN
    INSERT INTO t1(rowid,a,b,c) VALUES(100,100,100,3);
  END;
  REPLACE INTO t1(rowid,a,b,c) VALUES(200,1,2,3);
} {1 {UNIQUE constraint failed: t1.c}}
integrity_check insert-17.4


finish_test