return regArg;
}
-
-/*
-** This function does the work of sqlite3WindowCodeStep() for all "ROWS"
-** window frame types except for "BETWEEN UNBOUNDED PRECEDING AND CURRENT
-** ROW". Pseudo-code for each follows.
-**
-** ROWS BETWEEN <expr1> PRECEDING AND <expr2> FOLLOWING
-**
-** ...
-** if( new partition ){
-** Gosub flush_partition
-** }
-** Insert (record in eph-table)
-** sqlite3WhereEnd()
-** Gosub flush_partition
-**
-** flush_partition:
-** Once {
-** OpenDup (iEphCsr -> csrStart)
-** OpenDup (iEphCsr -> csrEnd)
-** }
-** regStart = <expr1> // PRECEDING expression
-** regEnd = <expr2> // FOLLOWING expression
-** if( regStart<0 || regEnd<0 ){ error! }
-** Rewind (csr,csrStart,csrEnd) // if EOF goto flush_partition_done
-** Next(csrEnd) // if EOF skip Aggstep
-** Aggstep (csrEnd)
-** if( (regEnd--)<=0 ){
-** AggFinal (xValue)
-** Gosub addrGosub
-** Next(csr) // if EOF goto flush_partition_done
-** if( (regStart--)<=0 ){
-** AggInverse (csrStart)
-** Next(csrStart)
-** }
-** }
-** flush_partition_done:
-** ResetSorter (csr)
-** Return
-**
-** ROWS BETWEEN <expr> PRECEDING AND CURRENT ROW
-** ROWS BETWEEN CURRENT ROW AND <expr> FOLLOWING
-** ROWS BETWEEN UNBOUNDED PRECEDING AND <expr> FOLLOWING
-**
-** These are similar to the above. For "CURRENT ROW", intialize the
-** register to 0. For "UNBOUNDED PRECEDING" to infinity.
-**
-** ROWS BETWEEN <expr> PRECEDING AND UNBOUNDED FOLLOWING
-** ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
-**
-** Rewind (csr,csrStart,csrEnd) // if EOF goto flush_partition_done
-** while( 1 ){
-** Next(csrEnd) // Exit while(1) at EOF
-** Aggstep (csrEnd)
-** }
-** while( 1 ){
-** AggFinal (xValue)
-** Gosub addrGosub
-** Next(csr) // if EOF goto flush_partition_done
-** if( (regStart--)<=0 ){
-** AggInverse (csrStart)
-** Next(csrStart)
-** }
-** }
-**
-** For the "CURRENT ROW AND UNBOUNDED FOLLOWING" case, the final if()
-** condition is always true (as if regStart were initialized to 0).
-**
-** RANGE BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
-**
-** This is the only RANGE case handled by this routine. It modifies the
-** second while( 1 ) loop in "ROWS BETWEEN CURRENT ... UNBOUNDED..." to
-** be:
-**
-** while( 1 ){
-** AggFinal (xValue)
-** while( 1 ){
-** regPeer++
-** Gosub addrGosub
-** Next(csr) // if EOF goto flush_partition_done
-** if( new peer ) break;
-** }
-** while( (regPeer--)>0 ){
-** AggInverse (csrStart)
-** Next(csrStart)
-** }
-** }
-**
-** ROWS BETWEEN <expr> FOLLOWING AND <expr> FOLLOWING
-**
-** regEnd = regEnd - regStart
-** Rewind (csr,csrStart,csrEnd) // if EOF goto flush_partition_done
-** Aggstep (csrEnd)
-** Next(csrEnd) // if EOF fall-through
-** if( (regEnd--)<=0 ){
-** if( (regStart--)<=0 ){
-** AggFinal (xValue)
-** Gosub addrGosub
-** Next(csr) // if EOF goto flush_partition_done
-** }
-** AggInverse (csrStart)
-** Next (csrStart)
-** }
-**
-** ROWS BETWEEN <expr> PRECEDING AND <expr> PRECEDING
-**
-** Replace the bit after "Rewind" in the above with:
-**
-** if( (regEnd--)<=0 ){
-** AggStep (csrEnd)
-** Next (csrEnd)
-** }
-** AggFinal (xValue)
-** Gosub addrGosub
-** Next(csr) // if EOF goto flush_partition_done
-** if( (regStart--)<=0 ){
-** AggInverse (csr2)
-** Next (csr2)
-** }
-**
-*/
-static void windowCodeRowExprStep(
- Parse *pParse,
- Select *p,
- WhereInfo *pWInfo,
- int regGosub,
- int addrGosub
-){
- Window *pMWin = p->pWin;
- Vdbe *v = sqlite3GetVdbe(pParse);
- int regFlushPart; /* Register for "Gosub flush_partition" */
- int lblFlushPart; /* Label for "Gosub flush_partition" */
- int lblFlushDone; /* Label for "Gosub flush_partition_done" */
-
- int regArg;
- int addr;
- int csrStart = pParse->nTab++;
- int csrEnd = pParse->nTab++;
- int regStart; /* Value of <expr> PRECEDING */
- int regEnd; /* Value of <expr> FOLLOWING */
- int addrGoto;
- int addrTop;
- int addrIfPos1 = 0;
- int addrIfPos2 = 0;
- int regSize = 0;
-
- assert( pMWin->eStart==TK_PRECEDING
- || pMWin->eStart==TK_CURRENT
- || pMWin->eStart==TK_FOLLOWING
- || pMWin->eStart==TK_UNBOUNDED
- );
- assert( pMWin->eEnd==TK_FOLLOWING
- || pMWin->eEnd==TK_CURRENT
- || pMWin->eEnd==TK_UNBOUNDED
- || pMWin->eEnd==TK_PRECEDING
- );
-
- /* Allocate register and label for the "flush_partition" sub-routine. */
- regFlushPart = ++pParse->nMem;
- lblFlushPart = sqlite3VdbeMakeLabel(pParse);
- lblFlushDone = sqlite3VdbeMakeLabel(pParse);
-
- regStart = ++pParse->nMem;
- regEnd = ++pParse->nMem;
-
- windowPartitionCache(pParse, p, pWInfo, regFlushPart, lblFlushPart, ®Size);
-
- addrGoto = sqlite3VdbeAddOp0(v, OP_Goto);
-
- /* Start of "flush_partition" */
- sqlite3VdbeResolveLabel(v, lblFlushPart);
- sqlite3VdbeAddOp2(v, OP_Once, 0, sqlite3VdbeCurrentAddr(v)+3);
- VdbeCoverage(v);
- VdbeComment((v, "Flush_partition subroutine"));
- sqlite3VdbeAddOp2(v, OP_OpenDup, csrStart, pMWin->iEphCsr);
- sqlite3VdbeAddOp2(v, OP_OpenDup, csrEnd, pMWin->iEphCsr);
-
- /* If either regStart or regEnd are not non-negative integers, throw
- ** an exception. */
- if( pMWin->pStart ){
- sqlite3ExprCode(pParse, pMWin->pStart, regStart);
- windowCheckIntValue(pParse, regStart, 0);
- }
- if( pMWin->pEnd ){
- sqlite3ExprCode(pParse, pMWin->pEnd, regEnd);
- windowCheckIntValue(pParse, regEnd, 1);
- }
-
- /* If this is "ROWS <expr1> FOLLOWING AND ROWS <expr2> FOLLOWING", do:
- **
- ** if( regEnd<regStart ){
- ** // The frame always consists of 0 rows
- ** regStart = regSize;
- ** }
- ** regEnd = regEnd - regStart;
- */
- if( pMWin->pEnd && pMWin->eStart==TK_FOLLOWING ){
- assert( pMWin->pStart!=0 );
- assert( pMWin->eEnd==TK_FOLLOWING );
- sqlite3VdbeAddOp3(v, OP_Ge, regStart, sqlite3VdbeCurrentAddr(v)+2, regEnd);
- VdbeCoverageNeverNull(v);
- sqlite3VdbeAddOp2(v, OP_Copy, regSize, regStart);
- sqlite3VdbeAddOp3(v, OP_Subtract, regStart, regEnd, regEnd);
- }
-
- if( pMWin->pStart && pMWin->eEnd==TK_PRECEDING ){
- assert( pMWin->pEnd!=0 );
- assert( pMWin->eStart==TK_PRECEDING );
- sqlite3VdbeAddOp3(v, OP_Le, regStart, sqlite3VdbeCurrentAddr(v)+3, regEnd);
- VdbeCoverageNeverNull(v);
- sqlite3VdbeAddOp2(v, OP_Copy, regSize, regStart);
- sqlite3VdbeAddOp2(v, OP_Copy, regSize, regEnd);
- }
-
- /* Initialize the accumulator register for each window function to NULL */
- regArg = windowInitAccum(pParse, pMWin);
-
- sqlite3VdbeAddOp2(v, OP_Rewind, pMWin->iEphCsr, lblFlushDone);
- VdbeCoverage(v);
- sqlite3VdbeAddOp2(v, OP_Rewind, csrStart, lblFlushDone);
- VdbeCoverageNeverTaken(v);
- sqlite3VdbeChangeP5(v, 1);
- sqlite3VdbeAddOp2(v, OP_Rewind, csrEnd, lblFlushDone);
- VdbeCoverageNeverTaken(v);
- sqlite3VdbeChangeP5(v, 1);
-
- /* Invoke AggStep function for each window function using the row that
- ** csrEnd currently points to. Or, if csrEnd is already at EOF,
- ** do nothing. */
- addrTop = sqlite3VdbeCurrentAddr(v);
- if( pMWin->eEnd==TK_PRECEDING ){
- addrIfPos1 = sqlite3VdbeAddOp3(v, OP_IfPos, regEnd, 0 , 1);
- VdbeCoverage(v);
- }
- sqlite3VdbeAddOp2(v, OP_Next, csrEnd, sqlite3VdbeCurrentAddr(v)+2);
- VdbeCoverage(v);
- addr = sqlite3VdbeAddOp0(v, OP_Goto);
- windowAggStep(pParse, pMWin, csrEnd, 0, regArg, regSize);
- if( pMWin->eEnd==TK_UNBOUNDED ){
- sqlite3VdbeAddOp2(v, OP_Goto, 0, addrTop);
- sqlite3VdbeJumpHere(v, addr);
- addrTop = sqlite3VdbeCurrentAddr(v);
- }else{
- sqlite3VdbeJumpHere(v, addr);
- if( pMWin->eEnd==TK_PRECEDING ){
- sqlite3VdbeJumpHere(v, addrIfPos1);
- }
- }
-
- if( pMWin->eEnd==TK_FOLLOWING ){
- addrIfPos1 = sqlite3VdbeAddOp3(v, OP_IfPos, regEnd, 0 , 1);
- VdbeCoverage(v);
- }
- if( pMWin->eStart==TK_FOLLOWING ){
- addrIfPos2 = sqlite3VdbeAddOp3(v, OP_IfPos, regStart, 0 , 1);
- VdbeCoverage(v);
- }
- windowAggFinal(pParse, pMWin, 0);
- windowReturnOneRow(pParse, pMWin, regGosub, addrGosub);
- sqlite3VdbeAddOp2(v, OP_Next, pMWin->iEphCsr, sqlite3VdbeCurrentAddr(v)+2);
- VdbeCoverage(v);
- sqlite3VdbeAddOp2(v, OP_Goto, 0, lblFlushDone);
- if( pMWin->eStart==TK_FOLLOWING ){
- sqlite3VdbeJumpHere(v, addrIfPos2);
- }
-
- if( pMWin->eStart==TK_CURRENT
- || pMWin->eStart==TK_PRECEDING
- || pMWin->eStart==TK_FOLLOWING
- ){
- int lblSkipInverse = sqlite3VdbeMakeLabel(pParse);;
- if( pMWin->eStart==TK_PRECEDING ){
- sqlite3VdbeAddOp3(v, OP_IfPos, regStart, lblSkipInverse, 1);
- VdbeCoverage(v);
- }
- if( pMWin->eStart==TK_FOLLOWING ){
- sqlite3VdbeAddOp2(v, OP_Next, csrStart, sqlite3VdbeCurrentAddr(v)+2);
- VdbeCoverage(v);
- sqlite3VdbeAddOp2(v, OP_Goto, 0, lblSkipInverse);
- }else{
- sqlite3VdbeAddOp2(v, OP_Next, csrStart, sqlite3VdbeCurrentAddr(v)+1);
- VdbeCoverageAlwaysTaken(v);
- }
- windowAggStep(pParse, pMWin, csrStart, 1, regArg, regSize);
- sqlite3VdbeResolveLabel(v, lblSkipInverse);
- }
- if( pMWin->eEnd==TK_FOLLOWING ){
- sqlite3VdbeJumpHere(v, addrIfPos1);
- }
- sqlite3VdbeAddOp2(v, OP_Goto, 0, addrTop);
-
- /* flush_partition_done: */
- sqlite3VdbeResolveLabel(v, lblFlushDone);
- sqlite3VdbeAddOp1(v, OP_ResetSorter, pMWin->iEphCsr);
- sqlite3VdbeAddOp1(v, OP_Return, regFlushPart);
- VdbeComment((v, "end flush_partition subroutine"));
-
- /* Jump to here to skip over flush_partition */
- sqlite3VdbeJumpHere(v, addrGoto);
-}
-
/*
** Return true if the entire partition should be cached in the ephemeral
** table before processing any rows.
int regCountdown,
int jumpOnEof
){
+ Window *pMWin = p->pMWin;
int ret = 0;
Vdbe *v = p->pVdbe;
int addrIf = 0;
+ /* Special case - WINDOW_AGGINVERSE is always a no-op if the frame
+ ** starts with UNBOUNDED PRECEDING. */
+ if( op==WINDOW_AGGINVERSE && pMWin->eStart==TK_UNBOUNDED ){
+ assert( regCountdown==0 && jumpOnEof==0 );
+ return 0;
+ }
+
if( regCountdown>0 ){
addrIf = sqlite3VdbeAddOp3(v, OP_IfPos, regCountdown, 0, 1);
}
switch( op ){
case WINDOW_RETURN_ROW:
- windowAggFinal(p->pParse, p->pMWin, 0);
- windowReturnOneRow(p->pParse, p->pMWin, p->regGosub, p->addrGosub);
+ windowAggFinal(p->pParse, pMWin, 0);
+ windowReturnOneRow(p->pParse, pMWin, p->regGosub, p->addrGosub);
break;
case WINDOW_AGGINVERSE:
- windowAggStep(p->pParse, p->pMWin, csr, 1, p->regArg, p->pMWin->regSize);
+ windowAggStep(p->pParse, pMWin, csr, 1, p->regArg, pMWin->regSize);
break;
case WINDOW_AGGSTEP:
- windowAggStep(p->pParse, p->pMWin, csr, 0, p->regArg, p->pMWin->regSize);
+ windowAggStep(p->pParse, pMWin, csr, 0, p->regArg, pMWin->regSize);
break;
}
int csrStart = csrCurrent+2;
int csrEnd = csrCurrent+3;
- int regStart; /* Value of <expr> PRECEDING */
- int regEnd; /* Value of <expr> FOLLOWING */
int iSubCsr = p->pSrc->a[0].iCursor; /* Cursor of sub-select */
int nSub = p->pSrc->a[0].pTab->nCol; /* Number of cols returned by sub */
int bCache = windowCachePartition(pMWin);
+ int regStart = 0; /* Value of <expr> PRECEDING */
+ int regEnd = 0; /* Value of <expr> FOLLOWING */
+
int reg = pParse->nMem+1;
int regRecord = reg+nSub;
int regRowid = regRecord+1;
pParse->nMem += 1 + nSub + 1;
regFlushPart = ++pParse->nMem;
- regStart = ++pParse->nMem;
- regEnd = ++pParse->nMem;
+
+ if( pMWin->eStart==TK_PRECEDING || pMWin->eStart==TK_FOLLOWING ){
+ regStart = ++pParse->nMem;
+ }
+ if( pMWin->eEnd==TK_PRECEDING || pMWin->eEnd==TK_FOLLOWING ){
+ regEnd = ++pParse->nMem;
+ }
assert( pMWin->eStart==TK_PRECEDING
|| pMWin->eStart==TK_CURRENT
/* This block is run for the first row of each partition */
s.regArg = regArg = windowInitAccum(pParse, pMWin);
- sqlite3ExprCode(pParse, pMWin->pStart, regStart);
- windowCheckIntValue(pParse, regStart, 0);
- sqlite3ExprCode(pParse, pMWin->pEnd, regEnd);
- windowCheckIntValue(pParse, regEnd, 1);
+ if( regStart ){
+ sqlite3ExprCode(pParse, pMWin->pStart, regStart);
+ windowCheckIntValue(pParse, regStart, 0);
+ }
+ if( regEnd ){
+ sqlite3ExprCode(pParse, pMWin->pEnd, regEnd);
+ windowCheckIntValue(pParse, regEnd, 1);
+ }
- if( pMWin->eStart==pMWin->eEnd
- && pMWin->eStart!=TK_CURRENT && pMWin->eStart!=TK_UNBOUNDED
- ){
+ if( pMWin->eStart==pMWin->eEnd && regStart && regEnd ){
int op = ((pMWin->eStart==TK_FOLLOWING) ? OP_Ge : OP_Le);
int addrGe = sqlite3VdbeAddOp3(v, op, regStart, 0, regEnd);
windowAggFinal(pParse, pMWin, 0);
addrShortcut = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, addrGe);
}
- if( pMWin->eStart==TK_FOLLOWING ){
+ if( pMWin->eStart==TK_FOLLOWING && regEnd ){
+ assert( pMWin->eEnd==TK_FOLLOWING );
sqlite3VdbeAddOp3(v, OP_Subtract, regStart, regEnd, regStart);
}
- sqlite3VdbeAddOp2(v, OP_Rewind, csrStart, 1);
+ if( pMWin->eStart!=TK_UNBOUNDED ){
+ sqlite3VdbeAddOp2(v, OP_Rewind, csrStart, 1);
+ }
sqlite3VdbeAddOp2(v, OP_Rewind, csrCurrent, 1);
sqlite3VdbeAddOp2(v, OP_Rewind, csrEnd, 1);
}
if( pMWin->eStart==TK_FOLLOWING ){
windowCodeOp(&s, WINDOW_AGGSTEP, csrEnd, 0, 0);
- windowCodeOp(&s, WINDOW_RETURN_ROW, csrCurrent, regEnd, 0);
- windowCodeOp(&s, WINDOW_AGGINVERSE, csrStart, regStart, 0);
+ if( pMWin->eEnd!=TK_UNBOUNDED ){
+ windowCodeOp(&s, WINDOW_RETURN_ROW, csrCurrent, regEnd, 0);
+ windowCodeOp(&s, WINDOW_AGGINVERSE, csrStart, regStart, 0);
+ }
}else
if( pMWin->eEnd==TK_PRECEDING ){
windowCodeOp(&s, WINDOW_AGGSTEP, csrEnd, regEnd, 0);
}else{
int addr;
windowCodeOp(&s, WINDOW_AGGSTEP, csrEnd, 0, 0);
- addr = sqlite3VdbeAddOp3(v, OP_IfPos, regEnd, 0, 1);
- windowCodeOp(&s, WINDOW_RETURN_ROW, csrCurrent, 0, 0);
- windowCodeOp(&s, WINDOW_AGGINVERSE, csrStart, regStart, 0);
- sqlite3VdbeJumpHere(v, addr);
+ if( pMWin->eEnd!=TK_UNBOUNDED ){
+ if( regEnd ) addr = sqlite3VdbeAddOp3(v, OP_IfPos, regEnd, 0, 1);
+ windowCodeOp(&s, WINDOW_RETURN_ROW, csrCurrent, 0, 0);
+ windowCodeOp(&s, WINDOW_AGGINVERSE, csrStart, regStart, 0);
+ if( regEnd ) sqlite3VdbeJumpHere(v, addr);
+ }
}
VdbeModuleComment((pParse->pVdbe, "End windowCodeStep.SECOND_ROW_CODE"));
int addrBreak2;
int addrBreak3;
windowCodeOp(&s, WINDOW_AGGSTEP, csrEnd, 0, 0);
- addrStart = sqlite3VdbeCurrentAddr(v);
- addrBreak1 = windowCodeOp(&s, WINDOW_RETURN_ROW, csrCurrent, regEnd, 1);
- addrBreak2 = windowCodeOp(&s, WINDOW_AGGINVERSE, csrStart, regStart, 1);
+ if( pMWin->eEnd==TK_UNBOUNDED ){
+ addrStart = sqlite3VdbeCurrentAddr(v);
+ addrBreak1 = windowCodeOp(&s, WINDOW_RETURN_ROW, csrCurrent, regStart, 1);
+ addrBreak2 = windowCodeOp(&s, WINDOW_AGGINVERSE, csrStart, 0, 1);
+ }else{
+ assert( pMWin->eEnd==TK_FOLLOWING );
+ addrStart = sqlite3VdbeCurrentAddr(v);
+ addrBreak1 = windowCodeOp(&s, WINDOW_RETURN_ROW, csrCurrent, regEnd, 1);
+ addrBreak2 = windowCodeOp(&s, WINDOW_AGGINVERSE, csrStart, regStart, 1);
+ }
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrStart);
sqlite3VdbeJumpHere(v, addrBreak2);
addrStart = sqlite3VdbeCurrentAddr(v);
** does not cache each partition in a temp table before beginning to
** return rows.
*/
- if( pMWin->eType==TK_ROWS
- && (pMWin->eStart!=TK_UNBOUNDED||pMWin->eEnd!=TK_CURRENT||!pMWin->pOrderBy)
- ){
- int bCache = windowCachePartition(pMWin);
- if( (pMWin->eEnd!=TK_FOLLOWING && pMWin->eEnd!=TK_PRECEDING)
- || (pMWin->eStart!=TK_FOLLOWING && pMWin->eStart!=TK_PRECEDING)
- ){
- VdbeModuleComment((pParse->pVdbe, "Begin RowExprStep()"));
- windowCodeRowExprStep(pParse, p, pWInfo, regGosub, addrGosub);
- VdbeModuleComment((pParse->pVdbe, "End RowExprStep()"));
- }else{
- VdbeModuleComment((pParse->pVdbe, "Begin windowCodeStep()"));
- windowCodeStep(pParse, p, pWInfo, regGosub, addrGosub);
- VdbeModuleComment((pParse->pVdbe, "End windowCodeStep()"));
- }
+ if( pMWin->eType==TK_ROWS ){
+ VdbeModuleComment((pParse->pVdbe, "Begin windowCodeStep()"));
+ windowCodeStep(pParse, p, pWInfo, regGosub, addrGosub);
+ VdbeModuleComment((pParse->pVdbe, "End windowCodeStep()"));
}else{
Window *pWin;
int bCache = 0; /* True to use CacheStep() */
projects / thirdparty / sqlite.git / commitdiff
