** We will have to generate an ephemeral table to do the job.
    */
    u32 savedNQueryLoop = pParse->nQueryLoop;
    int rMayHaveNull = 0;
    eType = IN_INDEX_EPH;
    if( inFlags & IN_INDEX_LOOP ){
      pParse->nQueryLoop = 0;
      if( pX->pLeft->iColumn<0 && !ExprHasProperty(pX, EP_xIsSelect) ){
        eType = IN_INDEX_ROWID;
      }
    }else if( prRhsHasNull ){
      *prRhsHasNull = rMayHaveNull = ++pParse->nMem;
    }
    assert( pX->op==TK_IN );
    sqlite3CodeRhsOfIN(pParse, pX, iTab, eType==IN_INDEX_ROWID);
    if( rMayHaveNull ){
      sqlite3SetHasNullFlag(v, iTab, rMayHaveNull);
    }
    pParse->nQueryLoop = savedNQueryLoop;
  }

  if( aiMap && eType!=IN_INDEX_INDEX_ASC && eType!=IN_INDEX_INDEX_DESC ){
................................................................................
**
** The pExpr parameter is the IN operator.  The cursor number for the
** constructed ephermeral table is returned.  The first time the ephemeral
** table is computed, the cursor number is also stored in pExpr->iTable,
** however the cursor number returned might not be the same, as it might
** have been duplicated using OP_OpenDup.
**
** If parameter isRowid is non-zero, then LHS of the IN operator is guaranteed
** to be a non-null integer. In this case, the ephemeral table can be an
** table B-Tree that keyed by only integers.  The more general cases uses
** an index B-Tree which can have arbitrary keys, but is slower to both
** read and write.
**
** If the LHS expression ("x" in the examples) is a column value, or
** the SELECT statement returns a column value, then the affinity of that
** column is used to build the index keys. If both 'x' and the
** SELECT... statement are columns, then numeric affinity is used
** if either column has NUMERIC or INTEGER affinity. If neither
** 'x' nor the SELECT... statement are columns, then numeric affinity
** is used.
*/
void sqlite3CodeRhsOfIN(
  Parse *pParse,          /* Parsing context */
  Expr *pExpr,            /* The IN operator */
  int iTab,               /* Use this cursor number */
  int isRowid             /* If true, LHS is a rowid */
){
  int addrOnce = 0;           /* Address of the OP_Once instruction at top */
  int addr;                   /* Address of OP_OpenEphemeral instruction */
  Expr *pLeft;                /* the LHS of the IN operator */
  KeyInfo *pKeyInfo = 0;      /* Key information */
  int nVal;                   /* Size of vector pLeft */
  Vdbe *v;                    /* The prepared statement under construction */
................................................................................

    addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
  }

  /* Check to see if this is a vector IN operator */
  pLeft = pExpr->pLeft;
  nVal = sqlite3ExprVectorSize(pLeft);
  assert( !isRowid || nVal==1 );

  /* Construct the ephemeral table that will contain the content of
  ** RHS of the IN operator.
  */
  pExpr->iTable = iTab;
  addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, 
      pExpr->iTable, (isRowid?0:nVal));
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  if( ExprHasProperty(pExpr, EP_xIsSelect) ){
    VdbeComment((v, "Result of SELECT %u", pExpr->x.pSelect->selId));
  }else{
    VdbeComment((v, "RHS of IN operator"));
  }
#endif
  pKeyInfo = isRowid ? 0 : sqlite3KeyInfoAlloc(pParse->db, nVal, 1);

  if( ExprHasProperty(pExpr, EP_xIsSelect) ){
    /* Case 1:     expr IN (SELECT ...)
    **
    ** Generate code to write the results of the select into the temporary
    ** table allocated and opened above.
    */
    Select *pSelect = pExpr->x.pSelect;
    ExprList *pEList = pSelect->pEList;

    ExplainQueryPlan((pParse, 1, "%sLIST SUBQUERY %d",
        addrOnce?"":"CORRELATED ", pSelect->selId
    ));
    assert( !isRowid );
    /* If the LHS and RHS of the IN operator do not match, that
    ** error will have been caught long before we reach this point. */
    if( ALWAYS(pEList->nExpr==nVal) ){
      SelectDest dest;
      int i;
      sqlite3SelectDestInit(&dest, SRT_Set, iTab);
      dest.zAffSdst = exprINAffinity(pParse, pExpr);
................................................................................
      assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
      pKeyInfo->aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
    }

    /* Loop through each expression in <exprlist>. */
    r1 = sqlite3GetTempReg(pParse);
    r2 = sqlite3GetTempReg(pParse);
    if( isRowid ) sqlite3VdbeAddOp4(v, OP_Blob, 0, r2, 0, "", P4_STATIC);
    for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
      Expr *pE2 = pItem->pExpr;
      int iValToIns;

      /* If the expression is not constant then we will need to
      ** disable the test that was generated above that makes sure
      ** this code only executes once.  Because for a non-constant
      ** expression we need to rerun this code each time.
      */
      if( addrOnce && !sqlite3ExprIsConstant(pE2) ){
        sqlite3VdbeChangeToNoop(v, addrOnce);
        addrOnce = 0;
      }

      /* Evaluate the expression and insert it into the temp table */
      if( isRowid && sqlite3ExprIsInteger(pE2, &iValToIns) ){
        sqlite3VdbeAddOp3(v, OP_InsertInt, iTab, r2, iValToIns);
      }else{
        r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);
        if( isRowid ){
          sqlite3VdbeAddOp2(v, OP_MustBeInt, r3,
                            sqlite3VdbeCurrentAddr(v)+2);
          VdbeCoverage(v);
          sqlite3VdbeAddOp3(v, OP_Insert, iTab, r2, r3);
        }else{
          sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1);
          sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iTab, r2, r3, 1);
        }
      }
    }
    sqlite3ReleaseTempReg(pParse, r1);
    sqlite3ReleaseTempReg(pParse, r2);
  }
  if( pKeyInfo ){
    sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO);
  }

    ** We will have to generate an ephemeral table to do the job.
    */
    u32 savedNQueryLoop = pParse->nQueryLoop;
    int rMayHaveNull = 0;
    eType = IN_INDEX_EPH;
    if( inFlags & IN_INDEX_LOOP ){
      pParse->nQueryLoop = 0;



    }else if( prRhsHasNull ){
      *prRhsHasNull = rMayHaveNull = ++pParse->nMem;
    }
    assert( pX->op==TK_IN );
    sqlite3CodeRhsOfIN(pParse, pX, iTab);
    if( rMayHaveNull ){
      sqlite3SetHasNullFlag(v, iTab, rMayHaveNull);
    }
    pParse->nQueryLoop = savedNQueryLoop;
  }

  if( aiMap && eType!=IN_INDEX_INDEX_ASC && eType!=IN_INDEX_INDEX_DESC ){
................................................................................
**
** The pExpr parameter is the IN operator.  The cursor number for the
** constructed ephermeral table is returned.  The first time the ephemeral
** table is computed, the cursor number is also stored in pExpr->iTable,
** however the cursor number returned might not be the same, as it might
** have been duplicated using OP_OpenDup.
**






** If the LHS expression ("x" in the examples) is a column value, or
** the SELECT statement returns a column value, then the affinity of that
** column is used to build the index keys. If both 'x' and the
** SELECT... statement are columns, then numeric affinity is used
** if either column has NUMERIC or INTEGER affinity. If neither
** 'x' nor the SELECT... statement are columns, then numeric affinity
** is used.
*/
void sqlite3CodeRhsOfIN(
  Parse *pParse,          /* Parsing context */
  Expr *pExpr,            /* The IN operator */
  int iTab                /* Use this cursor number */

){
  int addrOnce = 0;           /* Address of the OP_Once instruction at top */
  int addr;                   /* Address of OP_OpenEphemeral instruction */
  Expr *pLeft;                /* the LHS of the IN operator */
  KeyInfo *pKeyInfo = 0;      /* Key information */
  int nVal;                   /* Size of vector pLeft */
  Vdbe *v;                    /* The prepared statement under construction */
................................................................................

    addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
  }

  /* Check to see if this is a vector IN operator */
  pLeft = pExpr->pLeft;
  nVal = sqlite3ExprVectorSize(pLeft);


  /* Construct the ephemeral table that will contain the content of
  ** RHS of the IN operator.
  */
  pExpr->iTable = iTab;
  addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, nVal);

#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  if( ExprHasProperty(pExpr, EP_xIsSelect) ){
    VdbeComment((v, "Result of SELECT %u", pExpr->x.pSelect->selId));
  }else{
    VdbeComment((v, "RHS of IN operator"));
  }
#endif
  pKeyInfo = sqlite3KeyInfoAlloc(pParse->db, nVal, 1);

  if( ExprHasProperty(pExpr, EP_xIsSelect) ){
    /* Case 1:     expr IN (SELECT ...)
    **
    ** Generate code to write the results of the select into the temporary
    ** table allocated and opened above.
    */
    Select *pSelect = pExpr->x.pSelect;
    ExprList *pEList = pSelect->pEList;

    ExplainQueryPlan((pParse, 1, "%sLIST SUBQUERY %d",
        addrOnce?"":"CORRELATED ", pSelect->selId
    ));

    /* If the LHS and RHS of the IN operator do not match, that
    ** error will have been caught long before we reach this point. */
    if( ALWAYS(pEList->nExpr==nVal) ){
      SelectDest dest;
      int i;
      sqlite3SelectDestInit(&dest, SRT_Set, iTab);
      dest.zAffSdst = exprINAffinity(pParse, pExpr);
................................................................................
      assert( sqlite3KeyInfoIsWriteable(pKeyInfo) );
      pKeyInfo->aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
    }

    /* Loop through each expression in <exprlist>. */
    r1 = sqlite3GetTempReg(pParse);
    r2 = sqlite3GetTempReg(pParse);

    for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
      Expr *pE2 = pItem->pExpr;


      /* If the expression is not constant then we will need to
      ** disable the test that was generated above that makes sure
      ** this code only executes once.  Because for a non-constant
      ** expression we need to rerun this code each time.
      */
      if( addrOnce && !sqlite3ExprIsConstant(pE2) ){
        sqlite3VdbeChangeToNoop(v, addrOnce);
        addrOnce = 0;
      }

      /* Evaluate the expression and insert it into the temp table */



      r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);






      sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1);
      sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iTab, r2, r3, 1);


    }
    sqlite3ReleaseTempReg(pParse, r1);
    sqlite3ReleaseTempReg(pParse, r2);
  }
  if( pKeyInfo ){
    sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO);
  }

    pik_flags = (useSeekResult ? OPFLAG_USESEEKRESULT : 0);
    if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){
      assert( pParse->nested==0 );
      pik_flags |= OPFLAG_NCHANGE;
      pik_flags |= (update_flags & OPFLAG_SAVEPOSITION);
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
      if( update_flags==0 ){


        sqlite3VdbeAddOp4(v, OP_InsertInt, 
            iIdxCur+i, aRegIdx[i], 0, (char*)pTab, P4_TABLE
        );
        sqlite3VdbeChangeP5(v, OPFLAG_ISNOOP);

      }
#endif
    }
    sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iIdxCur+i, aRegIdx[i],
                         aRegIdx[i]+1,
                         pIdx->uniqNotNull ? pIdx->nKeyCol: pIdx->nColumn);
    sqlite3VdbeChangeP5(v, pik_flags);

    pik_flags = (useSeekResult ? OPFLAG_USESEEKRESULT : 0);
    if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){
      assert( pParse->nested==0 );
      pik_flags |= OPFLAG_NCHANGE;
      pik_flags |= (update_flags & OPFLAG_SAVEPOSITION);
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
      if( update_flags==0 ){
        int r = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp2(v, OP_Integer, 0, r);
        sqlite3VdbeAddOp4(v, OP_Insert, 
            iIdxCur+i, aRegIdx[i], r, (char*)pTab, P4_TABLE
        );
        sqlite3VdbeChangeP5(v, OPFLAG_ISNOOP);
        sqlite3ReleaseTempReg(pParse, r);
      }
#endif
    }
    sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iIdxCur+i, aRegIdx[i],
                         aRegIdx[i]+1,
                         pIdx->uniqNotNull ? pIdx->nKeyCol: pIdx->nColumn);
    sqlite3VdbeChangeP5(v, pik_flags);

void sqlite3Reindex(Parse*, Token*, Token*);
void sqlite3AlterFunctions(void);
void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
void sqlite3AlterRenameColumn(Parse*, SrcList*, Token*, Token*);
int sqlite3GetToken(const unsigned char *, int *);
void sqlite3NestedParse(Parse*, const char*, ...);
void sqlite3ExpirePreparedStatements(sqlite3*, int);
void sqlite3CodeRhsOfIN(Parse*, Expr*, int, int);
int sqlite3CodeSubselect(Parse*, Expr*);
void sqlite3SelectPrep(Parse*, Select*, NameContext*);
void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p);
int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
int sqlite3ResolveExprNames(NameContext*, Expr*);
int sqlite3ResolveExprListNames(NameContext*, ExprList*);
void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);

void sqlite3Reindex(Parse*, Token*, Token*);
void sqlite3AlterFunctions(void);
void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
void sqlite3AlterRenameColumn(Parse*, SrcList*, Token*, Token*);
int sqlite3GetToken(const unsigned char *, int *);
void sqlite3NestedParse(Parse*, const char*, ...);
void sqlite3ExpirePreparedStatements(sqlite3*, int);
void sqlite3CodeRhsOfIN(Parse*, Expr*, int);
int sqlite3CodeSubselect(Parse*, Expr*);
void sqlite3SelectPrep(Parse*, Select*, NameContext*);
void sqlite3SelectWrongNumTermsError(Parse *pParse, Select *p);
int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
int sqlite3ResolveExprNames(NameContext*, Expr*);
int sqlite3ResolveExprListNames(NameContext*, ExprList*);
void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);

** and register P2 becomes ephemeral.  If the cursor is changed, the
** value of register P2 will then change.  Make sure this does not
** cause any problems.)
**
** This instruction only works on tables.  The equivalent instruction
** for indices is OP_IdxInsert.
*/
/* Opcode: InsertInt P1 P2 P3 P4 P5
** Synopsis: intkey=P3 data=r[P2]
**
** This works exactly like OP_Insert except that the key is the
** integer value P3, not the value of the integer stored in register P3.
*/
case OP_Insert: 
case OP_InsertInt: {
  Mem *pData;       /* MEM cell holding data for the record to be inserted */
  Mem *pKey;        /* MEM cell holding key  for the record */
  VdbeCursor *pC;   /* Cursor to table into which insert is written */
  int seekResult;   /* Result of prior seek or 0 if no USESEEKRESULT flag */
  const char *zDb;  /* database name - used by the update hook */
  Table *pTab;      /* Table structure - used by update and pre-update hooks */
  BtreePayload x;   /* Payload to be inserted */
................................................................................
  assert( pC->eCurType==CURTYPE_BTREE );
  assert( pC->uc.pCursor!=0 );
  assert( (pOp->p5 & OPFLAG_ISNOOP) || pC->isTable );
  assert( pOp->p4type==P4_TABLE || pOp->p4type>=P4_STATIC );
  REGISTER_TRACE(pOp->p2, pData);
  sqlite3VdbeIncrWriteCounter(p, pC);

  if( pOp->opcode==OP_Insert ){
    pKey = &aMem[pOp->p3];
    assert( pKey->flags & MEM_Int );
    assert( memIsValid(pKey) );
    REGISTER_TRACE(pOp->p3, pKey);
    x.nKey = pKey->u.i;
  }else{
    assert( pOp->opcode==OP_InsertInt );
    x.nKey = pOp->p3;
  }

  if( pOp->p4type==P4_TABLE && HAS_UPDATE_HOOK(db) ){
    assert( pC->iDb>=0 );
    zDb = db->aDb[pC->iDb].zDbSName;
    pTab = pOp->p4.pTab;
    assert( (pOp->p5 & OPFLAG_ISNOOP) || HasRowid(pTab) );
  }else{

** and register P2 becomes ephemeral.  If the cursor is changed, the
** value of register P2 will then change.  Make sure this does not
** cause any problems.)
**
** This instruction only works on tables.  The equivalent instruction
** for indices is OP_IdxInsert.
*/






case OP_Insert: {

  Mem *pData;       /* MEM cell holding data for the record to be inserted */
  Mem *pKey;        /* MEM cell holding key  for the record */
  VdbeCursor *pC;   /* Cursor to table into which insert is written */
  int seekResult;   /* Result of prior seek or 0 if no USESEEKRESULT flag */
  const char *zDb;  /* database name - used by the update hook */
  Table *pTab;      /* Table structure - used by update and pre-update hooks */
  BtreePayload x;   /* Payload to be inserted */
................................................................................
  assert( pC->eCurType==CURTYPE_BTREE );
  assert( pC->uc.pCursor!=0 );
  assert( (pOp->p5 & OPFLAG_ISNOOP) || pC->isTable );
  assert( pOp->p4type==P4_TABLE || pOp->p4type>=P4_STATIC );
  REGISTER_TRACE(pOp->p2, pData);
  sqlite3VdbeIncrWriteCounter(p, pC);


  pKey = &aMem[pOp->p3];
  assert( pKey->flags & MEM_Int );
  assert( memIsValid(pKey) );
  REGISTER_TRACE(pOp->p3, pKey);
  x.nKey = pKey->u.i;





  if( pOp->p4type==P4_TABLE && HAS_UPDATE_HOOK(db) ){
    assert( pC->iDb>=0 );
    zDb = db->aDb[pC->iDb].zDbSName;
    pTab = pOp->p4.pTab;
    assert( (pOp->p5 & OPFLAG_ISNOOP) || HasRowid(pTab) );
  }else{

    if( pIn ){
      int iMap = 0;               /* Index in aiMap[] */
      pIn += i;
      for(i=iEq;i<pLoop->nLTerm; i++){
        if( pLoop->aLTerm[i]->pExpr==pX ){
          int iOut = iReg + i - iEq;
          if( eType==IN_INDEX_ROWID ){
            testcase( nEq>1 );  /* Happens with a UNIQUE index on ROWID */
            pIn->addrInTop = sqlite3VdbeAddOp2(v, OP_Rowid, iTab, iOut);
          }else{
            int iCol = aiMap ? aiMap[iMap++] : 0;
            pIn->addrInTop = sqlite3VdbeAddOp3(v,OP_Column,iTab, iCol, iOut);
          }
          sqlite3VdbeAddOp1(v, OP_IsNull, iOut); VdbeCoverage(v);
          if( i==iEq ){
................................................................................
    iReleaseReg = ++pParse->nMem;
    iRowidReg = codeEqualityTerm(pParse, pTerm, pLevel, 0, bRev, iReleaseReg);
    if( iRowidReg!=iReleaseReg ) sqlite3ReleaseTempReg(pParse, iReleaseReg);
    addrNxt = pLevel->addrNxt;
    sqlite3VdbeAddOp3(v, OP_SeekRowid, iCur, addrNxt, iRowidReg);
    VdbeCoverage(v);
    pLevel->op = OP_Noop;

    pTerm->wtFlags |= TERM_CODED;

  }else if( (pLoop->wsFlags & WHERE_IPK)!=0
         && (pLoop->wsFlags & WHERE_COLUMN_RANGE)!=0
  ){
    /* Case 3:  We have an inequality comparison against the ROWID field.
    */
    int testOp = OP_Noop;
    int start;

    if( pIn ){
      int iMap = 0;               /* Index in aiMap[] */
      pIn += i;
      for(i=iEq;i<pLoop->nLTerm; i++){
        if( pLoop->aLTerm[i]->pExpr==pX ){
          int iOut = iReg + i - iEq;
          if( eType==IN_INDEX_ROWID ){

            pIn->addrInTop = sqlite3VdbeAddOp2(v, OP_Rowid, iTab, iOut);
          }else{
            int iCol = aiMap ? aiMap[iMap++] : 0;
            pIn->addrInTop = sqlite3VdbeAddOp3(v,OP_Column,iTab, iCol, iOut);
          }
          sqlite3VdbeAddOp1(v, OP_IsNull, iOut); VdbeCoverage(v);
          if( i==iEq ){
................................................................................
    iReleaseReg = ++pParse->nMem;
    iRowidReg = codeEqualityTerm(pParse, pTerm, pLevel, 0, bRev, iReleaseReg);
    if( iRowidReg!=iReleaseReg ) sqlite3ReleaseTempReg(pParse, iReleaseReg);
    addrNxt = pLevel->addrNxt;
    sqlite3VdbeAddOp3(v, OP_SeekRowid, iCur, addrNxt, iRowidReg);
    VdbeCoverage(v);
    pLevel->op = OP_Noop;
    if( (pTerm->prereqAll & pLevel->notReady)==0 ){
      pTerm->wtFlags |= TERM_CODED;
    }
  }else if( (pLoop->wsFlags & WHERE_IPK)!=0
         && (pLoop->wsFlags & WHERE_COLUMN_RANGE)!=0
  ){
    /* Case 3:  We have an inequality comparison against the ROWID field.
    */
    int testOp = OP_Noop;
    int start;

  CREATE TABLE t1(a INT);
  CREATE INDEX t1a ON t1(a);
  INSERT INTO t1(a) VALUES(NULL),(NULL),(42),(NULL),(NULL);
  CREATE TABLE t2(dummy INT);
  SELECT count(*) FROM t1 LEFT JOIN t2 ON a IS NOT NULL;
} {5}














finish_test

  CREATE TABLE t1(a INT);
  CREATE INDEX t1a ON t1(a);
  INSERT INTO t1(a) VALUES(NULL),(NULL),(42),(NULL),(NULL);
  CREATE TABLE t2(dummy INT);
  SELECT count(*) FROM t1 LEFT JOIN t2 ON a IS NOT NULL;
} {5}

# 20190-02-22:  A bug introduced by checkin
# https://www.sqlite.org/src/info/fa792714ae62fa98.
#
do_execsql_test where-23.0 {
  DROP TABLE IF EXISTS t1;
  DROP TABLE IF EXISTS t2;
  CREATE TABLE t1(a INTEGER PRIMARY KEY);
  INSERT INTO t1(a) VALUES(1),(2),(3);
  CREATE TABLE t2(x INTEGER PRIMARY KEY, y INT);
  INSERT INTO t2(y) VALUES(2),(3);
  SELECT * FROM t1, t2 WHERE a=y AND y=3;
} {3 2 3}

finish_test