SQLite

        iKey = ++pParse->nMem;
        nKey = 0;   /* Zero tells OP_Found to use a composite key */
        sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey,
            sqlite3IndexAffinityStr(pParse->db, pPk), nPk);
        sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iEphCur, iKey, iPk, nPk);
      }else{
        /* Add the rowid of the row to be deleted to the RowSet */
        nKey = 1;  /* OP_DeferredSeek always uses a single rowid */
        sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
      }
    }
  
    /* If this DELETE cannot use the ONEPASS strategy, this is the 
    ** end of the WHERE loop */
    if( eOnePass!=ONEPASS_OFF ){

  u32 avail;         /* Number of bytes of available data */
  u32 t;             /* A type code from the record header */
  Mem *pReg;         /* PseudoTable input register */

  pC = p->apCsr[pOp->p1];
  p2 = pOp->p2;

  /* If the cursor cache is stale (meaning it is not currently point at
  ** the correct row) then bring it up-to-date by doing the necessary 
  ** B-Tree seek. */
  rc = sqlite3VdbeCursorMoveto(&pC, &p2);
  if( rc ) goto abort_due_to_error;

  assert( pOp->p3>0 && pOp->p3<=(p->nMem+1 - p->nCursor) );
  pDest = &aMem[pOp->p3];
  memAboutToChange(p, pDest);
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );

  }
  assert( pC->deferredMoveto==0 );
  pC->cacheStatus = CACHE_STALE;
  pC->seekResult = 0;
  break;
}

/* Opcode: DeferredSeek P1 * P3 P4 *
** Synopsis: Move P3 to P1.rowid if needed
**
** P1 is an open index cursor and P3 is a cursor on the corresponding
** table.  This opcode does a deferred seek of the P3 table cursor
** to the row that corresponds to the current row of P1.
**
** This is a deferred seek.  Nothing actually happens until
** the cursor is used to read a record.  That way, if no reads

**
** Write into register P2 an integer which is the last entry in the record at
** the end of the index key pointed to by cursor P1.  This integer should be
** the rowid of the table entry to which this index entry points.
**
** See also: Rowid, MakeRecord.
*/
case OP_DeferredSeek:
case OP_IdxRowid: {           /* out2 */
  VdbeCursor *pC;             /* The P1 index cursor */
  VdbeCursor *pTabCur;        /* The P2 table cursor (OP_DeferredSeek only) */
  i64 rowid;                  /* Rowid that P1 current points to */

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
  assert( pC!=0 );
  assert( pC->eCurType==CURTYPE_BTREE );
  assert( pC->uc.pCursor!=0 );
  assert( pC->isTable==0 );

  if( !pC->nullRow ){
    rowid = 0;  /* Not needed.  Only used to silence a warning. */
    rc = sqlite3VdbeIdxRowid(db, pC->uc.pCursor, &rowid);
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
    if( pOp->opcode==OP_DeferredSeek ){
      assert( pOp->p3>=0 && pOp->p3<p->nCursor );
      pTabCur = p->apCsr[pOp->p3];
      assert( pTabCur!=0 );
      assert( pTabCur->eCurType==CURTYPE_BTREE );
      assert( pTabCur->uc.pCursor!=0 );
      assert( pTabCur->isTable );
      pTabCur->nullRow = 0;

** Cursor iCur is open on an intkey b-tree (a table). Register iRowid contains
** a rowid value just read from cursor iIdxCur, open on index pIdx. This
** function generates code to do a deferred seek of cursor iCur to the 
** rowid stored in register iRowid.
**
** Normally, this is just:
**
**   OP_DeferredSeek $iCur $iRowid
**
** However, if the scan currently being coded is a branch of an OR-loop and
** the statement currently being coded is a SELECT, then P3 of OP_DeferredSeek
** is set to iIdxCur and P4 is set to point to an array of integers
** containing one entry for each column of the table cursor iCur is open 
** on. For each table column, if the column is the i'th column of the 
** index, then the corresponding array entry is set to (i+1). If the column
** does not appear in the index at all, the array entry is set to 0.
*/
static void codeDeferredSeek(
  WhereInfo *pWInfo,              /* Where clause context */
  Index *pIdx,                    /* Index scan is using */
  int iCur,                       /* Cursor for IPK b-tree */
  int iIdxCur                     /* Index cursor */
){
  Parse *pParse = pWInfo->pParse; /* Parse context */
  Vdbe *v = pParse->pVdbe;        /* Vdbe to generate code within */

  assert( iIdxCur>0 );
  assert( pIdx->aiColumn[pIdx->nColumn-1]==-1 );
  
  sqlite3VdbeAddOp3(v, OP_DeferredSeek, iIdxCur, 0, iCur);
  if( (pWInfo->wctrlFlags & WHERE_OR_SUBCLAUSE)
   && DbMaskAllZero(sqlite3ParseToplevel(pParse)->writeMask)
  ){
    int i;
    Table *pTab = pIdx->pTable;
    int *ai = (int*)sqlite3DbMallocZero(pParse->db, sizeof(int)*(pTab->nCol+1));
    if( ai ){