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Improvements to the way built-in window functions are handled.

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FossilOrigin-Name: e8eee566dfca6f4c8af074731dfe91f7fbcd9ca72f0303235b52e4e2e80d5b71
This commit is contained in:
dan
2019-03-06 17:12:32 +00:00
parent b25a214dec
commit b33487b0b6
5 changed files with 95 additions and 52 deletions
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125
src/window.c
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@@ -1092,6 +1092,8 @@ void sqlite3WindowCodeInit(Parse *pParse, Window *pMWin){
pMWin->regFirst = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 1, pMWin->regFirst);
pMWin->regSize = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, pMWin->regSize);
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
FuncDef *p = pWin->pFunc;
@@ -1841,6 +1843,26 @@ static void windowCodeRowExprStep(
sqlite3VdbeJumpHere(v, addrGoto);
}
/*
** Return true if the entire partition should be cached in the temp
** table before processing.
*/
static int windowCachePartition(Window *pMWin){
Window *pWin;
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
FuncDef *pFunc = pWin->pFunc;
if( (pFunc->funcFlags & SQLITE_FUNC_WINDOW_SIZE)
|| (pFunc->zName==nth_valueName)
|| (pFunc->zName==first_valueName)
|| (pFunc->zName==leadName)
|| (pFunc->zName==lagName)
){
return 1;
}
}
return 0;
}
static void windowCodeStep(
Parse *pParse,
Select *p,
@@ -1871,13 +1893,19 @@ static void windowCodeStep(
int addrIfStart;
int addrGosubFlush;
int addrInteger;
int addrCacheRewind;
int addrCacheNext;
int addrShortcut = 0;
int bCache = windowCachePartition(pMWin);
int reg = pParse->nMem+1;
int regRecord = reg+nSub;
int regRowid = regRecord+1;
bCache = 1;
pParse->nMem += 1 + nSub + 1;
regFlushPart = ++pParse->nMem;
@@ -1903,7 +1931,12 @@ static void windowCodeStep(
}
sqlite3VdbeAddOp3(v, OP_MakeRecord, reg, nSub, regRecord);
/* Check if the current iteration is the first row of a new partition */
/* An input row has just been read into an array of registers starting
** at reg. If the window has a PARTITION clause, this block generates
** VM code to check if the input row is the start of a new partition.
** If so, it does an OP_Gosub to an address to be filled in later. The
** address of the OP_Gosub is stored in local variable addrGosubFlush.
*/
if( pMWin->pPartition ){
int addr;
ExprList *pPart = pMWin->pPartition;
@@ -1914,25 +1947,32 @@ static void windowCodeStep(
addrIf = sqlite3VdbeAddOp1(v, OP_If, pMWin->regFirst);
addr = sqlite3VdbeAddOp3(v, OP_Compare, regNewPart, pMWin->regPart, nPart);
sqlite3VdbeAppendP4(v, (void*)pKeyInfo, P4_KEYINFO);
sqlite3VdbeAddOp3(v, OP_Jump, addr+2, addr+3, addr+2);
sqlite3VdbeAddOp3(v, OP_Jump, addr+2, addr+4, addr+2);
VdbeCoverageEqNe(v);
addrGosubFlush = sqlite3VdbeAddOp1(v, OP_Gosub, regFlushPart);
VdbeComment((v, "call flush_partition"));
sqlite3VdbeJumpHere(v, addrIf);
sqlite3VdbeAddOp3(v, OP_Copy, regNewPart, pMWin->regPart, nPart-1);
}
/* Insert the new row into the ephemeral table */
sqlite3VdbeAddOp2(v, OP_NewRowid, csrWrite, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, csrWrite, regRecord, regRowid);
sqlite3VdbeAddOp2(v, OP_AddImm, pMWin->regSize, 1);
/* This block is run for the first row of each partition */
addrIf = sqlite3VdbeAddOp1(v, OP_IfNot, pMWin->regFirst);
if( pMWin->pPartition ){
sqlite3VdbeAddOp3(v, OP_Copy,
reg+pMWin->nBufferCol, pMWin->regPart, pMWin->pPartition->nExpr-1
);
if( bCache ){
sqlite3VdbeAddOp2(v, OP_Integer, 0, pMWin->regFirst);
sqlite3WhereEnd(pWInfo);
addrInteger = sqlite3VdbeAddOp2(v, OP_Integer, 0, regFlushPart);
if( pMWin->pPartition ){
sqlite3VdbeJumpHere(v, addrGosubFlush);
}
addrCacheRewind = sqlite3VdbeAddOp1(v, OP_Rewind, csrWrite);
}else{
addrIf = sqlite3VdbeAddOp1(v, OP_IfNot, pMWin->regFirst);
}
/* This block is run for the first row of each partition */
regArg = windowInitAccum(pParse, pMWin);
sqlite3ExprCode(pParse, pMWin->pStart, regStart);
@@ -1944,9 +1984,16 @@ static void windowCodeStep(
int op = ((pMWin->eStart==TK_FOLLOWING) ? OP_Ge : OP_Le);
int addrGe = sqlite3VdbeAddOp3(v, op, regStart, 0, regEnd);
windowAggFinal(pParse, pMWin, 0);
sqlite3VdbeAddOp2(v, OP_Rewind, csrCurrent, 1);
windowReturnOneRow(pParse, pMWin, regGosub, addrGosub);
sqlite3VdbeAddOp1(v, OP_ResetSorter, csrCurrent);
if( bCache ){
sqlite3VdbeAddOp2(v, OP_Rowid, csrWrite, regRowid);
sqlite3VdbeAddOp3(v, OP_NotExists, csrCurrent, 0, regRowid);
windowReturnOneRow(pParse, pMWin, regGosub, addrGosub);
sqlite3VdbeAddOp2(v, OP_Next, csrWrite, addrCacheRewind+1);
}else{
sqlite3VdbeAddOp2(v, OP_Rewind, csrCurrent, 1);
windowReturnOneRow(pParse, pMWin, regGosub, addrGosub);
sqlite3VdbeAddOp1(v, OP_ResetSorter, csrCurrent);
}
addrShortcut = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, addrGe);
}
@@ -1962,7 +2009,11 @@ static void windowCodeStep(
addrGoto = sqlite3VdbeAddOp0(v, OP_Goto);
/* This block is run for the second and subsequent rows of each partition */
sqlite3VdbeJumpHere(v, addrIf);
if( bCache ){
addrCacheNext = sqlite3VdbeCurrentAddr(v);
}else{
sqlite3VdbeJumpHere(v, addrIf);
}
if( pMWin->eStart==TK_FOLLOWING ){
addrIfEnd = sqlite3VdbeAddOp3(v, OP_IfPos, regEnd, 0, 1);
@@ -1973,13 +2024,13 @@ static void windowCodeStep(
addrIfStart = sqlite3VdbeAddOp3(v, OP_IfPos, regStart, 0, 1);
sqlite3VdbeAddOp2(v, OP_Next, csrStart, sqlite3VdbeCurrentAddr(v)+1);
windowAggStep(pParse, pMWin, csrStart, 1, regArg, 0);
windowAggStep(pParse, pMWin, csrStart, 1, regArg, pMWin->regSize);
sqlite3VdbeJumpHere(v, addrIfStart);
}else
if( pMWin->eEnd==TK_PRECEDING ){
addrIfEnd = sqlite3VdbeAddOp3(v, OP_IfPos, regEnd, 0, 1);
sqlite3VdbeAddOp2(v, OP_Next, csrEnd, sqlite3VdbeCurrentAddr(v)+1);
windowAggStep(pParse, pMWin, csrEnd, 0, regArg, 0);
windowAggStep(pParse, pMWin, csrEnd, 0, regArg, pMWin->regSize);
sqlite3VdbeJumpHere(v, addrIfEnd);
windowAggFinal(pParse, pMWin, 0);
@@ -1988,7 +2039,7 @@ static void windowCodeStep(
addrIfStart = sqlite3VdbeAddOp3(v, OP_IfPos, regStart, 0, 1);
sqlite3VdbeAddOp2(v, OP_Next, csrStart, sqlite3VdbeCurrentAddr(v)+1);
windowAggStep(pParse, pMWin, csrStart, 1, regArg, 0);
windowAggStep(pParse, pMWin, csrStart, 1, regArg, pMWin->regSize);
sqlite3VdbeJumpHere(v, addrIfStart);
}else{
addrIfEnd = sqlite3VdbeAddOp3(v, OP_IfPos, regEnd, 0, 1);
@@ -1997,7 +2048,7 @@ static void windowCodeStep(
windowReturnOneRow(pParse, pMWin, regGosub, addrGosub);
addrIfStart = sqlite3VdbeAddOp3(v, OP_IfPos, regStart, 0, 1);
sqlite3VdbeAddOp2(v, OP_Next, csrStart, sqlite3VdbeCurrentAddr(v)+1);
windowAggStep(pParse, pMWin, csrStart, 1, regArg, 0);
windowAggStep(pParse, pMWin, csrStart, 1, regArg, pMWin->regSize);
sqlite3VdbeJumpHere(v, addrIfStart);
sqlite3VdbeJumpHere(v, addrIfEnd);
}
@@ -2005,16 +2056,21 @@ static void windowCodeStep(
sqlite3VdbeJumpHere(v, addrGoto);
if( pMWin->eEnd!=TK_PRECEDING ){
sqlite3VdbeAddOp2(v, OP_Next, csrEnd, sqlite3VdbeCurrentAddr(v)+1);
windowAggStep(pParse, pMWin, csrEnd, 0, regArg, 0);
windowAggStep(pParse, pMWin, csrEnd, 0, regArg, pMWin->regSize);
}
/* End of the main input loop */
if( addrShortcut>0 ) sqlite3VdbeJumpHere(v, addrShortcut);
sqlite3WhereEnd(pWInfo);
if( bCache ){
sqlite3VdbeAddOp2(v, OP_Next, csrWrite, addrCacheNext);
sqlite3VdbeJumpHere(v, addrCacheRewind);
}else{
if( addrShortcut>0 ) sqlite3VdbeJumpHere(v, addrShortcut);
sqlite3WhereEnd(pWInfo);
}
/* Fall through */
if( pMWin->pPartition ){
if( pMWin->pPartition && bCache==0 ){
addrInteger = sqlite3VdbeAddOp2(v, OP_Integer, 0, regFlushPart);
sqlite3VdbeJumpHere(v, addrGosubFlush);
}
@@ -2031,7 +2087,7 @@ static void windowCodeStep(
addrIfStart = sqlite3VdbeAddOp3(v, OP_IfPos, regStart, 0, 1);
sqlite3VdbeAddOp2(v, OP_Next, csrStart, sqlite3VdbeCurrentAddr(v)+2);
sqlite3VdbeAddOp0(v, OP_Goto);
windowAggStep(pParse, pMWin, csrStart, 1, regArg, 0);
windowAggStep(pParse, pMWin, csrStart, 1, regArg, pMWin->regSize);
sqlite3VdbeJumpHere(v, addrIfStart);
sqlite3VdbeJumpHere(v, addrIfStart+2);
@@ -2043,7 +2099,7 @@ static void windowCodeStep(
if( pMWin->eEnd==TK_PRECEDING ){
addrIfEnd = sqlite3VdbeAddOp3(v, OP_IfPos, regEnd, 0, 1);
sqlite3VdbeAddOp2(v, OP_Next, csrEnd, sqlite3VdbeCurrentAddr(v)+1);
windowAggStep(pParse, pMWin, csrEnd, 0, regArg, 0);
windowAggStep(pParse, pMWin, csrEnd, 0, regArg, pMWin->regSize);
sqlite3VdbeJumpHere(v, addrIfEnd);
windowAggFinal(pParse, pMWin, 0);
windowReturnOneRow(pParse, pMWin, regGosub, addrGosub);
@@ -2052,7 +2108,7 @@ static void windowCodeStep(
windowReturnOneRow(pParse, pMWin, regGosub, addrGosub);
addrIfStart = sqlite3VdbeAddOp3(v, OP_IfPos, regStart, 0, 1);
sqlite3VdbeAddOp2(v, OP_Next, csrStart, sqlite3VdbeCurrentAddr(v)+1);
windowAggStep(pParse, pMWin, csrStart, 1, regArg, 0);
windowAggStep(pParse, pMWin, csrStart, 1, regArg, pMWin->regSize);
sqlite3VdbeJumpHere(v, addrIfStart);
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrGoto-1);
}
@@ -2060,8 +2116,10 @@ static void windowCodeStep(
}
if( bCache && addrShortcut>0 ) sqlite3VdbeJumpHere(v, addrShortcut);
sqlite3VdbeAddOp1(v, OP_ResetSorter, csrCurrent);
sqlite3VdbeAddOp2(v, OP_Integer, 1, pMWin->regFirst);
sqlite3VdbeAddOp2(v, OP_Integer, 0, pMWin->regSize);
if( bCache==0 ) sqlite3VdbeAddOp2(v, OP_Integer, 1, pMWin->regFirst);
if( pMWin->pPartition ){
sqlite3VdbeChangeP1(v, addrInteger, sqlite3VdbeCurrentAddr(v));
sqlite3VdbeAddOp1(v, OP_Return, regFlushPart);
@@ -2530,23 +2588,8 @@ void sqlite3WindowCodeStep(
if( pMWin->eType==TK_ROWS
&& (pMWin->eStart!=TK_UNBOUNDED||pMWin->eEnd!=TK_CURRENT||!pMWin->pOrderBy)
){
Window *pWin;
int bCache = 0; /* True to use CacheStep() */
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
FuncDef *pFunc = pWin->pFunc;
if( (pFunc->funcFlags & SQLITE_FUNC_WINDOW_SIZE)
|| (pFunc->zName==nth_valueName)
|| (pFunc->zName==first_valueName)
|| (pFunc->zName==leadName)
|| (pFunc->zName==lagName)
){
bCache = 1;
break;
}
}
if( bCache
|| (pMWin->eStart!=TK_PRECEDING && pMWin->eStart!=TK_FOLLOWING)
|| (pMWin->eEnd!=TK_FOLLOWING && pMWin->eEnd!=TK_PRECEDING)
if( (pMWin->eStart!=TK_PRECEDING && pMWin->eStart!=TK_FOLLOWING)
|| (pMWin->eEnd!=TK_FOLLOWING && pMWin->eEnd!=TK_PRECEDING)
){
VdbeModuleComment((pParse->pVdbe, "Begin RowExprStep()"));
windowCodeRowExprStep(pParse, p, pWInfo, regGosub, addrGosub);