SQLite

** with the object passed as the only argument to this function.
*/
static int windowArgCount(Window *pWin){
  ExprList *pList = pWin->pOwner->x.pList;
  return (pList ? pList->nExpr : 0);
}



















































































































typedef struct WindowCodeArg WindowCodeArg;
typedef struct WindowCsrAndReg WindowCsrAndReg;

/*
** See comments above struct WindowCodeArg.
*/
struct WindowCsrAndReg {

  Parse *pParse;             /* Parse context */
  Window *pMWin;             /* First in list of functions being processed */
  Vdbe *pVdbe;               /* VDBE object */
  int addrGosub;             /* OP_Gosub to this address to return one row */
  int regGosub;              /* Register used with OP_Gosub(addrGosub) */
  int regArg;                /* First in array of accumulator registers */
  int eDelete;               /* See above */
  int regStart;              /* Value of <expr> PRECEDING */
  int regEnd;                /* Value of <expr> FOLLOWING */

  WindowCsrAndReg start;
  WindowCsrAndReg current;
  WindowCsrAndReg end;
};








/*
** Generate VM code to read the window frames peer values from cursor csr into
** an array of registers starting at reg.
*/
static void windowReadPeerValues(
  WindowCodeArg *p,
  int csr,

    int i;
    for(i=0; i<pOrderBy->nExpr; i++){
      sqlite3VdbeAddOp3(v, OP_Column, csr, iColOff+i, reg+i);
    }
  }
}

/*
** Generate VM code to invoke either xStep() (if bInverse is 0) or 
** xInverse (if bInverse is non-zero) for each window function in the 
** linked list starting at pMWin. Or, for built-in window functions
** that do not use the standard function API, generate the required
** inline VM code.
**
** If argument csr is greater than or equal to 0, then argument reg is
** the first register in an array of registers guaranteed to be large
** enough to hold the array of arguments for each function. In this case
** the arguments are extracted from the current row of csr into the
** array of registers before invoking OP_AggStep or OP_AggInverse
**
** Or, if csr is less than zero, then the array of registers at reg is
** already populated with all columns from the current row of the sub-query.
**
** If argument regPartSize is non-zero, then it is a register containing the
** number of rows in the current partition.
*/
static void windowAggStep(
  WindowCodeArg *p,
  Window *pMWin,                  /* Linked list of window functions */
  int csr,                        /* Read arguments from this cursor */
  int bInverse,                   /* True to invoke xInverse instead of xStep */
  int reg                         /* Array of registers */
){
  Parse *pParse = p->pParse;
  Vdbe *v = sqlite3GetVdbe(pParse);
  Window *pWin;
  for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
    FuncDef *pFunc = pWin->pFunc;
    int regArg;
    int nArg = pWin->bExprArgs ? 0 : windowArgCount(pWin);
    int i;

    assert( bInverse==0 || pWin->eStart!=TK_UNBOUNDED );

    for(i=0; i<nArg; i++){
      if( i!=1 || pFunc->zName!=nth_valueName ){
        sqlite3VdbeAddOp3(v, OP_Column, csr, pWin->iArgCol+i, reg+i);
      }else{
        sqlite3VdbeAddOp3(v, OP_Column, pMWin->iEphCsr, pWin->iArgCol+i, reg+i);
      }
    }
    regArg = reg;

    if( pMWin->regStartRowid==0
     && (pFunc->funcFlags & SQLITE_FUNC_MINMAX) 
     && (pWin->eStart!=TK_UNBOUNDED)
    ){
      int addrIsNull = sqlite3VdbeAddOp1(v, OP_IsNull, regArg);
      VdbeCoverage(v);
      if( bInverse==0 ){
        sqlite3VdbeAddOp2(v, OP_AddImm, pWin->regApp+1, 1);
        sqlite3VdbeAddOp2(v, OP_SCopy, regArg, pWin->regApp);
        sqlite3VdbeAddOp3(v, OP_MakeRecord, pWin->regApp, 2, pWin->regApp+2);
        sqlite3VdbeAddOp2(v, OP_IdxInsert, pWin->csrApp, pWin->regApp+2);
      }else{
        sqlite3VdbeAddOp4Int(v, OP_SeekGE, pWin->csrApp, 0, regArg, 1);
        VdbeCoverageNeverTaken(v);
        sqlite3VdbeAddOp1(v, OP_Delete, pWin->csrApp);
        sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-2);
      }
      sqlite3VdbeJumpHere(v, addrIsNull);
    }else if( pWin->regApp ){
      assert( pFunc->zName==nth_valueName
           || pFunc->zName==first_valueName
      );
      assert( bInverse==0 || bInverse==1 );
      sqlite3VdbeAddOp2(v, OP_AddImm, pWin->regApp+1-bInverse, 1);
    }else if( pFunc->xSFunc!=noopStepFunc ){
      int addrIf = 0;
      int addrIf2 = 0;
      if( pWin->pFilter ){
        int regTmp;
        assert( pWin->bExprArgs || !nArg ||nArg==pWin->pOwner->x.pList->nExpr );
        assert( pWin->bExprArgs || nArg  ||pWin->pOwner->x.pList==0 );
        regTmp = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp3(v, OP_Column, csr, pWin->iArgCol+nArg,regTmp);
        addrIf = sqlite3VdbeAddOp3(v, OP_IfNot, regTmp, 0, 1);
        VdbeCoverage(v);
        sqlite3ReleaseTempReg(pParse, regTmp);
      }

      
      /* If this is a (RANGE BETWEEN a PRECEDING AND b PRECEDING) or a
      ** (RANGE BETWEEN b FOLLOWING AND a FOLLOWING) frame and (b > a), 
      ** omit the OP_AggStep or OP_AggInverse if the peer value is numeric.
      ** A numeric peer value is one for which the following is true: 
      **
      **    (peer IS NOT NULL AND peer < '')
      */
      if( pWin->eFrmType==TK_RANGE 
       && pWin->eStart==pWin->eEnd 
       && pWin->eStart==TK_PRECEDING
      ){
        int op = ((pMWin->eStart==TK_FOLLOWING) ? OP_Ge : OP_Le);
        int regPeer = sqlite3GetTempReg(pParse);
        int regString = sqlite3GetTempReg(pParse);
        int lbl = sqlite3VdbeMakeLabel(pParse);
        VdbeModuleComment((v, "windowAggStep \"peer is numeric?\" test"));
        sqlite3VdbeAddOp3(v, op, p->regStart, lbl, p->regEnd);
        VdbeCoverageNeverNullIf(v, op==OP_Ge); /* NeverNull because <expr> */
        VdbeCoverageNeverNullIf(v, op==OP_Le); /*   values previously checked */
        windowReadPeerValues(p, csr, regPeer);
        sqlite3VdbeAddOp2(v, OP_IsNull, regPeer, lbl);
        sqlite3VdbeAddOp4(v, OP_String8, 0, regString, 0, "", P4_STATIC);
        addrIf2 = sqlite3VdbeAddOp3(v, OP_Lt, regString, 0, regPeer);
        sqlite3ReleaseTempReg(pParse, regPeer);
        sqlite3ReleaseTempReg(pParse, regString);
        sqlite3VdbeResolveLabel(v, lbl);
        VdbeModuleComment((v, "windowAggStep end \"peer is numeric?\""));
        assert( pWin->eStart==TK_PRECEDING || pWin->eStart==TK_FOLLOWING );
        assert( pMWin->pOrderBy && pMWin->pOrderBy->nExpr==1 );
      }

      if( pWin->bExprArgs ){
        int iStart = sqlite3VdbeCurrentAddr(v);
        VdbeOp *pOp, *pEnd;

        nArg = pWin->pOwner->x.pList->nExpr;
        regArg = sqlite3GetTempRange(pParse, nArg);
        sqlite3ExprCodeExprList(pParse, pWin->pOwner->x.pList, regArg, 0, 0);

        pEnd = sqlite3VdbeGetOp(v, -1);
        for(pOp=sqlite3VdbeGetOp(v, iStart); pOp<=pEnd; pOp++){
          if( pOp->opcode==OP_Column && pOp->p1==pWin->iEphCsr ){
            pOp->p1 = csr;
          }
        }
      }
      if( pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL ){
        CollSeq *pColl;
        assert( nArg>0 );
        pColl = sqlite3ExprNNCollSeq(pParse, pWin->pOwner->x.pList->a[0].pExpr);
        sqlite3VdbeAddOp4(v, OP_CollSeq, 0,0,0, (const char*)pColl, P4_COLLSEQ);
      }
      sqlite3VdbeAddOp3(v, bInverse? OP_AggInverse : OP_AggStep, 
                        bInverse, regArg, pWin->regAccum);
      sqlite3VdbeAppendP4(v, pFunc, P4_FUNCDEF);
      sqlite3VdbeChangeP5(v, (u8)nArg);
      if( pWin->bExprArgs ){
        sqlite3ReleaseTempRange(pParse, regArg, nArg);
      }
      if( addrIf ) sqlite3VdbeJumpHere(v, addrIf);
      if( addrIf2 ) sqlite3VdbeJumpHere(v, addrIf2);
    }
  }
}

/*
** Values that may be passed as the second argument to windowCodeOp().
*/
#define WINDOW_RETURN_ROW 1
#define WINDOW_AGGINVERSE 2
#define WINDOW_AGGSTEP    3

/*
** Generate VM code to invoke either xValue() (bFin==0) or xFinalize()
** (bFin==1) for each window function in the linked list starting at
** pMWin. Or, for built-in window-functions that do not use the standard
** API, generate the equivalent VM code.
*/
static void windowAggFinal(WindowCodeArg *p, int bFin){

  int nPeer;
  int lblNext;
  int lblBrk;
  int addrNext;
  int csr;

  VdbeModuleComment((v, "windowFullScan begin"));

  assert( pMWin!=0 );
  csr = pMWin->csrApp;
  nPeer = (pMWin->pOrderBy ? pMWin->pOrderBy->nExpr : 0);

  lblNext = sqlite3VdbeMakeLabel(pParse);
  lblBrk = sqlite3VdbeMakeLabel(pParse);

      VdbeCoverageEqNe(v);
    }else{
      sqlite3VdbeAddOp2(v, OP_Goto, 0, lblNext);
    }
    if( addrEq ) sqlite3VdbeJumpHere(v, addrEq);
  }

  windowAggStep(p, pMWin, csr, 0, p->regArg);

  sqlite3VdbeResolveLabel(v, lblNext);
  sqlite3VdbeAddOp2(v, OP_Next, csr, addrNext);
  VdbeCoverage(v);
  sqlite3VdbeJumpHere(v, addrNext-1);
  sqlite3VdbeJumpHere(v, addrNext+1);
  sqlite3ReleaseTempReg(pParse, regRowid);
  sqlite3ReleaseTempReg(pParse, regCRowid);
  if( nPeer ){
    sqlite3ReleaseTempRange(pParse, regPeer, nPeer);
    sqlite3ReleaseTempRange(pParse, regCPeer, nPeer);
  }

  windowAggFinal(p, 1);
  VdbeModuleComment((v, "windowFullScan end"));
}

/*
** Invoke the sub-routine at regGosub (generated by code in select.c) to
** return the current row of Window.iEphCsr. If all window functions are
** aggregate window functions that use the standard API, a single
** OP_Gosub instruction is all that this routine generates. Extra VM code

 int jumpOnEof                    /* Jump here if stepped cursor reaches EOF */
){
  int csr, reg;
  Parse *pParse = p->pParse;
  Window *pMWin = p->pMWin;
  int ret = 0;
  Vdbe *v = p->pVdbe;

  int addrContinue = 0;

  int bPeer = (pMWin->eFrmType!=TK_ROWS);

  int lblDone = sqlite3VdbeMakeLabel(pParse);
  int addrNextRange = 0;

  /* Special case - WINDOW_AGGINVERSE is always a no-op if the frame
  ** starts with UNBOUNDED PRECEDING. */

        }
      }else{
        windowCodeRangeTest(
            p, OP_Gt, p->end.csr, regCountdown, p->current.csr, lblDone
        );
      }
    }else{
      sqlite3VdbeAddOp3(v, OP_IfPos, regCountdown, lblDone, 1);
      VdbeCoverage(v);
    }
  }

  if( op==WINDOW_RETURN_ROW && pMWin->regStartRowid==0 ){
    windowAggFinal(p, 0);
  }

    case WINDOW_AGGINVERSE:
      csr = p->start.csr;
      reg = p->start.reg;
      if( pMWin->regStartRowid ){
        assert( pMWin->regEndRowid );
        sqlite3VdbeAddOp2(v, OP_AddImm, pMWin->regStartRowid, 1);
      }else{
        windowAggStep(p, pMWin, csr, 1, p->regArg);
      }
      break;

    default:
      assert( op==WINDOW_AGGSTEP );
      csr = p->end.csr;
      reg = p->end.reg;
      if( pMWin->regStartRowid ){
        assert( pMWin->regEndRowid );
        sqlite3VdbeAddOp2(v, OP_AddImm, pMWin->regEndRowid, 1);
      }else{
        windowAggStep(p, pMWin, csr, 0, p->regArg);
      }
      break;
  }

  if( op==p->eDelete ){
    sqlite3VdbeAddOp1(v, OP_Delete, csr);
    sqlite3VdbeChangeP5(v, OPFLAG_SAVEPOSITION);
  }

  if( jumpOnEof ){
    sqlite3VdbeAddOp2(v, OP_Next, csr, sqlite3VdbeCurrentAddr(v)+2);
    VdbeCoverage(v);
    ret = sqlite3VdbeAddOp0(v, OP_Goto);
  }else{
    sqlite3VdbeAddOp2(v, OP_Next, csr, sqlite3VdbeCurrentAddr(v)+1+bPeer);
    VdbeCoverage(v);
    if( bPeer ){
      sqlite3VdbeAddOp2(v, OP_Goto, 0, lblDone);
    }
  }

  if( bPeer ){
    int nReg = (pMWin->pOrderBy ? pMWin->pOrderBy->nExpr : 0);
    int regTmp;

    /* If this is a (RANGE BETWEEN a FOLLOWING AND b FOLLOWING), ensure
    ** the start cursor does not advance past the end cursor within the
    ** temporary table. It otherwise might, if (a>b).  */
    if( pMWin->eStart==TK_FOLLOWING && pMWin->eEnd==TK_FOLLOWING
     && pMWin->eFrmType==TK_RANGE && op==WINDOW_AGGINVERSE
    ){
      int regRowid1 = sqlite3GetTempReg(pParse);
      int regRowid2 = sqlite3GetTempReg(pParse);
      sqlite3VdbeAddOp2(v, OP_Rowid, p->start.csr, regRowid1);
      sqlite3VdbeAddOp2(v, OP_Rowid, p->end.csr, regRowid2);
      sqlite3VdbeAddOp3(v, OP_Ge, regRowid2, lblDone, regRowid1);
      sqlite3ReleaseTempReg(pParse, regRowid1);
      sqlite3ReleaseTempReg(pParse, regRowid2);
    }
    regTmp = (nReg ? sqlite3GetTempRange(pParse, nReg) : 0);
    windowReadPeerValues(p, csr, regTmp);
    windowIfNewPeer(pParse, pMWin->pOrderBy, regTmp, reg, addrContinue);
    sqlite3ReleaseTempRange(pParse, regTmp, nReg);
  }

  if( addrNextRange ){
    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrNextRange);
  }
  sqlite3VdbeResolveLabel(v, lblDone);


  return ret;
}


/*
** Allocate and return a duplicate of the Window object indicated by the
** third argument. Set the Window.pOwner field of the new object to

**       }
**       Insert new row into eph table.
**       if( first row of partition ){
**         Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
**         regEnd = <expr2>
**         regStart = <expr1>
**       }else{
**         while( (csrEnd.key + regEnd) <= csrCurrent.key ){
**           AGGSTEP
**         }
**         RETURN_ROW
**         while( (csrStart.key + regStart) < csrCurrent.key ){
**           AGGINVERSE
**         }

**       }
**     }
**     flush:
**       while( (csrEnd.key + regEnd) <= csrCurrent.key ){
**         AGGSTEP
**       }
**       RETURN_ROW
**       while( (csrStart.key + regStart) < csrCurrent.key ){
**         AGGINVERSE
**       }

**
**   RANGE BETWEEN <expr1> FOLLOWING AND <expr2> FOLLOWING
**
**     ... loop started by sqlite3WhereBegin() ...
**       if( new partition ){
**         Gosub flush
**       }

  int csrInput = p->pSrc->a[0].iCursor;     /* Cursor of sub-select */
  int nInput = p->pSrc->a[0].pTab->nCol;    /* Number of cols returned by sub */
  int iInput;                               /* To iterate through sub cols */
  int addrNe;                     /* Address of OP_Ne */
  int addrGosubFlush = 0;         /* Address of OP_Gosub to flush: */
  int addrInteger = 0;            /* Address of OP_Integer */
  int addrEmpty;                  /* Address of OP_Rewind in flush: */


  int regNew;                     /* Array of registers holding new input row */
  int regRecord;                  /* regNew array in record form */
  int regRowid;                   /* Rowid for regRecord in eph table */
  int regNewPeer = 0;             /* Peer values for new row (part of regNew) */
  int regPeer = 0;                /* Peer values for current row */
  int regFlushPart = 0;           /* Register for "Gosub flush_partition" */
  WindowCodeArg s;                /* Context object for sub-routines */

  regRecord = ++pParse->nMem;
  regRowid = ++pParse->nMem;

  /* If the window frame contains an "<expr> PRECEDING" or "<expr> FOLLOWING"
  ** clause, allocate registers to store the results of evaluating each
  ** <expr>.  */
  if( pMWin->eStart==TK_PRECEDING || pMWin->eStart==TK_FOLLOWING ){
    s.regStart = ++pParse->nMem;
  }
  if( pMWin->eEnd==TK_PRECEDING || pMWin->eEnd==TK_FOLLOWING ){
    s.regEnd = ++pParse->nMem;
  }

  /* If this is not a "ROWS BETWEEN ..." frame, then allocate arrays of
  ** registers to store copies of the ORDER BY expressions (peer values) 
  ** for the main loop, and for each cursor (start, current and end). */
  if( pMWin->eFrmType!=TK_ROWS ){
    int nPeer = (pOrderBy ? pOrderBy->nExpr : 0);

  sqlite3VdbeAddOp3(v, OP_Insert, csrWrite, regRecord, regRowid);
  addrNe = sqlite3VdbeAddOp3(v, OP_Ne, pMWin->regOne, 0, regRowid);
  VdbeCoverageNeverNull(v);

  /* This block is run for the first row of each partition */
  s.regArg = windowInitAccum(pParse, pMWin);

  if( s.regStart ){
    sqlite3ExprCode(pParse, pMWin->pStart, s.regStart);
    windowCheckValue(pParse, s.regStart, 0 + (pMWin->eFrmType==TK_RANGE?3:0));
  }
  if( s.regEnd ){
    sqlite3ExprCode(pParse, pMWin->pEnd, s.regEnd);
    windowCheckValue(pParse, s.regEnd, 1 + (pMWin->eFrmType==TK_RANGE?3:0));
  }

  if( pMWin->eFrmType!=TK_RANGE && pMWin->eStart==pMWin->eEnd && s.regStart ){
    int op = ((pMWin->eStart==TK_FOLLOWING) ? OP_Ge : OP_Le);
    int addrGe = sqlite3VdbeAddOp3(v, op, s.regStart, 0, s.regEnd);
    VdbeCoverageNeverNullIf(v, op==OP_Ge); /* NeverNull because bound <expr> */
    VdbeCoverageNeverNullIf(v, op==OP_Le); /*   values previously checked */
    windowAggFinal(&s, 0);
    sqlite3VdbeAddOp2(v, OP_Rewind, s.current.csr, 1);
    VdbeCoverageNeverTaken(v);
    windowReturnOneRow(&s);
    sqlite3VdbeAddOp1(v, OP_ResetSorter, s.current.csr);
    sqlite3VdbeAddOp2(v, OP_Goto, 0, lblWhereEnd);
    sqlite3VdbeJumpHere(v, addrGe);
  }
  if( pMWin->eStart==TK_FOLLOWING && pMWin->eFrmType!=TK_RANGE && s.regEnd ){
    assert( pMWin->eEnd==TK_FOLLOWING );
    sqlite3VdbeAddOp3(v, OP_Subtract, s.regStart, s.regEnd, s.regStart);
  }

  if( pMWin->eStart!=TK_UNBOUNDED ){
    sqlite3VdbeAddOp2(v, OP_Rewind, s.start.csr, 1);
    VdbeCoverageNeverTaken(v);
  }
  sqlite3VdbeAddOp2(v, OP_Rewind, s.current.csr, 1);

  }
  if( pMWin->eStart==TK_FOLLOWING ){
    windowCodeOp(&s, WINDOW_AGGSTEP, 0, 0);
    if( pMWin->eEnd!=TK_UNBOUNDED ){
      if( pMWin->eFrmType==TK_RANGE ){
        int lbl = sqlite3VdbeMakeLabel(pParse);
        int addrNext = sqlite3VdbeCurrentAddr(v);
        windowCodeRangeTest(&s, OP_Ge, s.current.csr, s.regEnd, s.end.csr, lbl);
        windowCodeOp(&s, WINDOW_AGGINVERSE, s.regStart, 0);
        windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 0);
        sqlite3VdbeAddOp2(v, OP_Goto, 0, addrNext);
        sqlite3VdbeResolveLabel(v, lbl);
      }else{
        windowCodeOp(&s, WINDOW_RETURN_ROW, s.regEnd, 0);
        windowCodeOp(&s, WINDOW_AGGINVERSE, s.regStart, 0);
      }
    }
  }else
  if( pMWin->eEnd==TK_PRECEDING ){
    int bRPS = (pMWin->eStart==TK_PRECEDING && pMWin->eFrmType==TK_RANGE);
    windowCodeOp(&s, WINDOW_AGGSTEP, s.regEnd, 0);
    if( bRPS ) windowCodeOp(&s, WINDOW_AGGINVERSE, s.regStart, 0);
    windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 0);
    if( !bRPS ) windowCodeOp(&s, WINDOW_AGGINVERSE, s.regStart, 0);
  }else{
    int addr = 0;
    windowCodeOp(&s, WINDOW_AGGSTEP, 0, 0);
    if( pMWin->eEnd!=TK_UNBOUNDED ){
      if( pMWin->eFrmType==TK_RANGE ){
        int lbl = 0;
        addr = sqlite3VdbeCurrentAddr(v);
        if( s.regEnd ){
          lbl = sqlite3VdbeMakeLabel(pParse);
          windowCodeRangeTest(&s, OP_Ge, s.current.csr,s.regEnd,s.end.csr,lbl);
        }
        windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 0);
        windowCodeOp(&s, WINDOW_AGGINVERSE, s.regStart, 0);
        if( s.regEnd ){
          sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
          sqlite3VdbeResolveLabel(v, lbl);
        }
      }else{
        if( s.regEnd ){
          addr = sqlite3VdbeAddOp3(v, OP_IfPos, s.regEnd, 0, 1);
          VdbeCoverage(v);
        }
        windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 0);
        windowCodeOp(&s, WINDOW_AGGINVERSE, s.regStart, 0);
        if( s.regEnd ) sqlite3VdbeJumpHere(v, addr);
      }
    }
  }

  /* End of the main input loop */
  sqlite3VdbeResolveLabel(v, lblWhereEnd);
  sqlite3WhereEnd(pWInfo);

  /* Fall through */
  if( pMWin->pPartition ){
    addrInteger = sqlite3VdbeAddOp2(v, OP_Integer, 0, regFlushPart);
    sqlite3VdbeJumpHere(v, addrGosubFlush);
  }

  addrEmpty = sqlite3VdbeAddOp1(v, OP_Rewind, csrWrite);
  VdbeCoverage(v);
  if( pMWin->eEnd==TK_PRECEDING ){
    int bRPS = (pMWin->eStart==TK_PRECEDING && pMWin->eFrmType==TK_RANGE);
    windowCodeOp(&s, WINDOW_AGGSTEP, s.regEnd, 0);
    if( bRPS ) windowCodeOp(&s, WINDOW_AGGINVERSE, s.regStart, 0);
    windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 0);
  }else if( pMWin->eStart==TK_FOLLOWING ){
    int addrStart;
    int addrBreak1;
    int addrBreak2;
    int addrBreak3;
    windowCodeOp(&s, WINDOW_AGGSTEP, 0, 0);
    if( pMWin->eFrmType==TK_RANGE ){
      addrStart = sqlite3VdbeCurrentAddr(v);
      addrBreak2 = windowCodeOp(&s, WINDOW_AGGINVERSE, s.regStart, 1);
      addrBreak1 = windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 1);
    }else
    if( pMWin->eEnd==TK_UNBOUNDED ){
      addrStart = sqlite3VdbeCurrentAddr(v);
      addrBreak1 = windowCodeOp(&s, WINDOW_RETURN_ROW, s.regStart, 1);
      addrBreak2 = windowCodeOp(&s, WINDOW_AGGINVERSE, 0, 1);
    }else{
      assert( pMWin->eEnd==TK_FOLLOWING );
      addrStart = sqlite3VdbeCurrentAddr(v);
      addrBreak1 = windowCodeOp(&s, WINDOW_RETURN_ROW, s.regEnd, 1);
      addrBreak2 = windowCodeOp(&s, WINDOW_AGGINVERSE, s.regStart, 1);
    }
    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrStart);
    sqlite3VdbeJumpHere(v, addrBreak2);
    addrStart = sqlite3VdbeCurrentAddr(v);
    addrBreak3 = windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 1);
    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrStart);
    sqlite3VdbeJumpHere(v, addrBreak1);
    sqlite3VdbeJumpHere(v, addrBreak3);
  }else{
    int addrBreak;
    int addrStart;
    windowCodeOp(&s, WINDOW_AGGSTEP, 0, 0);
    addrStart = sqlite3VdbeCurrentAddr(v);
    addrBreak = windowCodeOp(&s, WINDOW_RETURN_ROW, 0, 1);
    windowCodeOp(&s, WINDOW_AGGINVERSE, s.regStart, 0);
    sqlite3VdbeAddOp2(v, OP_Goto, 0, addrStart);
    sqlite3VdbeJumpHere(v, addrBreak);
  }
  sqlite3VdbeJumpHere(v, addrEmpty);

  sqlite3VdbeAddOp1(v, OP_ResetSorter, s.current.csr);
  if( pMWin->pPartition ){

  BY fake_column))
  SELECT * FROM y;
} {1 {no such column: fake_column}}

do_catchsql_test 4.3 {
  SELECT 1 WINDOW win AS (PARTITION BY fake_column);
} {0 1}

#-------------------------------------------------------------------------
reset_db
do_execsql_test 5.0 {
  CREATE TABLE t1(a, c);
  CREATE INDEX i1 ON t1(a);

  INSERT INTO t1 VALUES(0, 421);
  INSERT INTO t1 VALUES(1, 844);
  INSERT INTO t1 VALUES(2, 1001);
}

do_execsql_test 5.1 {
  SELECT a, sum(c) OVER (
    ORDER BY a RANGE BETWEEN 0 PRECEDING AND 3 PRECEDING
  ) FROM t1;
} {0 {} 1 {} 2 {}}

do_execsql_test 5.2 {
  INSERT INTO t1 VALUES(NULL, 123);
  INSERT INTO t1 VALUES(NULL, 111);
  INSERT INTO t1 VALUES('xyz', 222);
  INSERT INTO t1 VALUES('xyz', 333);

  SELECT a, sum(c) OVER (
    ORDER BY a RANGE BETWEEN 0 PRECEDING AND 3 PRECEDING
  ) FROM t1;
} {{} 234 {} 234 0 {} 1 {} 2 {} xyz 555 xyz 555}

do_execsql_test 5.3 {
  SELECT a, sum(c) OVER (
    ORDER BY a RANGE BETWEEN 2 FOLLOWING AND 0 FOLLOWING
  ) FROM t1;
} {{} 234 {} 234 0 {} 1 {} 2 {} xyz 555 xyz 555}

do_execsql_test 5.4 {
  SELECT a, sum(c) OVER (
    ORDER BY a RANGE BETWEEN 0 PRECEDING AND 3 PRECEDING EXCLUDE NO OTHERS
  ) FROM t1;
} {{} 234 {} 234 0 {} 1 {} 2 {} xyz 555 xyz 555}

do_execsql_test 5.5 {
  SELECT a, sum(c) OVER (
    ORDER BY a RANGE BETWEEN 2 FOLLOWING AND 0 FOLLOWING EXCLUDE NO OTHERS
  ) FROM t1;
} {{} 234 {} 234 0 {} 1 {} 2 {} xyz 555 xyz 555}

#-------------------------------------------------------------------------
reset_db
do_execsql_test 6.0 {
  CREATE TABLE t1(a, c);
  CREATE INDEX i1 ON t1(a);

  INSERT INTO t1 VALUES(7,  997);
  INSERT INTO t1 VALUES(8,  997);
  INSERT INTO t1 VALUES('abc', 1001);
}
do_execsql_test 6.1 {
  SELECT a, sum(c) OVER (
    ORDER BY a RANGE BETWEEN 2 FOLLOWING AND 0 FOLLOWING 
  ) FROM t1;
} {7 {} 8 {} abc 1001} 
do_execsql_test 6.2 {
  SELECT a, sum(c) OVER (
    ORDER BY a RANGE BETWEEN 2 FOLLOWING AND 0 FOLLOWING EXCLUDE NO OTHERS
  ) FROM t1;
} {7 {} 8 {} abc 1001} 

finish_test