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Fix a bug in the KEYINFO handling within select.c. Change the OP_Move

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opcode to take a count and to move multiple registers.  Initial code for
the compound-select merge optimization is added but is incomplete
and is commented out. (CVS 5272)

FossilOrigin-Name: 663a590e3086145a57af7569d8f798b6b6a8b76c
This commit is contained in:
drh
2008-06-22 12:37:57 +00:00
parent 04bcc00788
commit b21e7c70f7
10 changed files with 424 additions and 73 deletions
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381
src/select.c
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@@ -12,7 +12,7 @@
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.432 2008/06/20 18:13:25 drh Exp $
** $Id: select.c,v 1.433 2008/06/22 12:37:58 drh Exp $
*/
#include "sqliteInt.h"
@@ -425,7 +425,7 @@ static void pushOntoSorter(
int regRecord = sqlite3GetTempReg(pParse);
sqlite3ExprCodeExprList(pParse, pOrderBy, regBase, 0);
sqlite3VdbeAddOp2(v, OP_Sequence, pOrderBy->iECursor, regBase+nExpr);
sqlite3ExprCodeMove(pParse, regData, regBase+nExpr+1);
sqlite3ExprCodeMove(pParse, regData, regBase+nExpr+1, 1);
sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nExpr + 2, regRecord);
sqlite3VdbeAddOp2(v, OP_IdxInsert, pOrderBy->iECursor, regRecord);
sqlite3ReleaseTempReg(pParse, regRecord);
@@ -693,7 +693,7 @@ static void selectInnerLoop(
if( pOrderBy ){
pushOntoSorter(pParse, pOrderBy, p, regResult);
}else{
sqlite3ExprCodeMove(pParse, regResult, iParm);
sqlite3ExprCodeMove(pParse, regResult, iParm, 1);
/* The LIMIT clause will jump out of the loop for us */
}
break;
@@ -841,7 +841,7 @@ static void generateSortTail(
}
case SRT_Mem: {
assert( nColumn==1 );
sqlite3ExprCodeMove(pParse, regRow, iParm);
sqlite3ExprCodeMove(pParse, regRow, iParm, 1);
/* The LIMIT clause will terminate the loop for us */
break;
}
@@ -1668,12 +1668,6 @@ static int processOrderGroupBy(
** Analyze and ORDER BY or GROUP BY clause in a SELECT statement. Return
** the number of errors seen.
**
** The processing depends on whether the SELECT is simple or compound.
** For a simple SELECT statement, evry term of the ORDER BY or GROUP BY
** clause needs to be an expression. If any expression is an integer
** constant, then that expression is replaced by the corresponding
** expression from the result set.
**
** For compound SELECT statements, every expression needs to be of
** type TK_COLUMN with a iTable value as given in the 4th parameter.
** If any expression is an integer, that becomes the column number.
@@ -1873,6 +1867,15 @@ static CollSeq *multiSelectCollSeq(Parse *pParse, Select *p, int iCol){
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */
/* Forward reference */
static int multiSelectOrderBy(
Parse *pParse, /* Parsing context */
Select *p, /* The right-most of SELECTs to be coded */
SelectDest *pDest, /* What to do with query results */
char *aff /* If eDest is SRT_Union, the affinity string */
);
#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** This routine is called to process a compound query form from
@@ -1920,8 +1923,6 @@ static int multiSelect(
int nSetP2 = 0; /* Number of slots in aSetP2[] used */
SelectDest dest; /* Alternative data destination */
dest = *pDest;
/* Make sure there is no ORDER BY or LIMIT clause on prior SELECTs. Only
** the last (right-most) SELECT in the series may have an ORDER BY or LIMIT.
*/
@@ -1953,8 +1954,15 @@ static int multiSelect(
goto multi_select_end;
}
#if 0
if( p->pOrderBy ){
return multiSelectOrderBy(pParse, p, pDest, aff);
}
#endif
/* Create the destination temporary table if necessary
*/
dest = *pDest;
if( dest.eDest==SRT_EphemTab ){
assert( p->pEList );
assert( nSetP2<sizeof(aSetP2)/sizeof(aSetP2[0]) );
@@ -2305,6 +2313,349 @@ multi_select_end:
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */
#if 0 /****** ################ ******/
/*
** Code an output subroutine for a coroutine implementation of a
** SELECT statment.
*/
static int outputSubroutine(
Parse *pParse,
SelectDest *pIn
SelectDest *pDest
){
Vdbe *v = pParse->pVdbe;
if( v==0 ) return;
if( pDest->iMem==0 ){
pDest->iMem = sqlite3GetTempRange(pParse, pIn->nMem);
pDest->nMem = nResultCol;
}
switch( pDest->eDest ){
/* Store the result as data using a unique key.
*/
case SRT_Table:
case SRT_EphemTab: {
int r1 = sqlite3GetTempReg(pParse);
int r2 = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
sqlite3VdbeAddOp2(v, OP_NewRowid, iParm, r2);
sqlite3VdbeAddOp3(v, OP_Insert, iParm, r1, r2);
sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
sqlite3ReleaseTempReg(pParse, r2);
sqlite3ReleaseTempReg(pParse, r1);
break;
}
#ifndef SQLITE_OMIT_SUBQUERY
/* If we are creating a set for an "expr IN (SELECT ...)" construct,
** then there should be a single item on the stack. Write this
** item into the set table with bogus data.
*/
case SRT_Set: {
int addr2, r1;
assert( nColumn==1 );
addr2 = sqlite3VdbeAddOp1(v, OP_IsNull, regResult);
p->affinity = sqlite3CompareAffinity(pEList->a[0].pExpr, pDest->affinity);
r1 = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp4(v, OP_MakeRecord, regResult, 1, r1, &p->affinity, 1);
sqlite3ExprCacheAffinityChange(pParse, regResult, 1);
sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, r1);
sqlite3ReleaseTempReg(pParse, r1);
sqlite3VdbeJumpHere(v, addr2);
break;
}
/* If any row exist in the result set, record that fact and abort.
*/
case SRT_Exists: {
sqlite3VdbeAddOp2(v, OP_Integer, 1, iParm);
/* The LIMIT clause will terminate the loop for us */
break;
}
/* If this is a scalar select that is part of an expression, then
** store the results in the appropriate memory cell and break out
** of the scan loop.
*/
case SRT_Mem: {
assert( nColumn==1 );
sqlite3ExprCodeMove(pParse, regResult, iParm, 1);
/* The LIMIT clause will jump out of the loop for us */
break;
}
#endif /* #ifndef SQLITE_OMIT_SUBQUERY */
/* Send the data to the callback function or to a subroutine. In the
** case of a subroutine, the subroutine itself is responsible for
** popping the data from the stack.
*/
case SRT_Coroutine:
case SRT_Callback: {
if( eDest==SRT_Coroutine ){
sqlite3VdbeAddOp1(v, OP_Yield, pDest->regCoroutine);
}else{
sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, nColumn);
sqlite3ExprCacheAffinityChange(pParse, regResult, nColumn);
}
break;
}
#if !defined(SQLITE_OMIT_TRIGGER)
/* Discard the results. This is used for SELECT statements inside
** the body of a TRIGGER. The purpose of such selects is to call
** user-defined functions that have side effects. We do not care
** about the actual results of the select.
*/
default: {
break;
}
#endif
}
}
/*
** Alternative compound select code generator for cases when there
** is an ORDER BY clause.
**
** We assume a query of the following form:
**
** <selectA> <operator> <selectB> ORDER BY <orderbylist>
**
** <operator> is one of UNION ALL, UNION, EXCEPT, or INTERSECT. The idea
** is to code both <selectA> and <selectB> with the ORDER BY clause as
** co-routines. Then run the co-routines in parallel and merge the results
** into the output. In addition to the two coroutines (called selectA and
** selectB) there are 7 subroutines:
**
** outA: Move the output of the selectA coroutine into the output
** of the compound query.
**
** outB: Move the output of the selectB coroutine into the output
** of the compound query. (Only generated for UNION and
** UNION ALL. EXCEPT and INSERTSECT never output a row that
** appears only in B.)
**
** AltB: Called when there is data from both coroutines and A<B.
**
** AeqB: Called when there is data from both coroutines and A==B.
**
** AgtB: Called when there is data from both coroutines and A>B.
**
** EofA: Called when data is exhausted from selectA.
**
** EofB: Called when data is exhausted from selectB.
**
** The implementation of the latter five subroutines depend on which
** <operator> is used:
**
**
** UNION ALL UNION EXCEPT INTERSECT
** ------------- ----------------- -------------- -----------------
** AltB: outA, nextA outA, nextA outA, nextA nextA
**
** AeqB: outA, nextA nextA nextA outA
** nextA while A==B
**
** AgtB: outB, nextB outB, nextB nextB nextB
**
** EofA: outB, nextB A<-B, outB, halt halt
** nextB while A==B
**
** EofB: outA, nextA B<-A, outA outA, nextA halt
** nextA while A==B
**
** The implementation plan is to implement the two coroutines and seven
** subroutines first, then put the control logic at the bottom. Like this:
**
** goto Init
** coA: coroutine for left query (A)
** coB: coroutine for right query (B)
** outA: output one row of A
** outB: output one row of B (UNION and UNION ALL only)
** EofA: ...
** EofB: ...
** AltB: ...
** AeqB: ...
** AgtB: ...
** Init: initialize coroutine registers
** yield coA
** if eof(A) goto EofA
** yield coB
** if eof(B) goto EofB
** Cmpr: Compare A, B
** Jump AltB, AeqB, AgtB
** End: ...
**
** We call AltB, AeqB, AgtB, EofA, and EofB "subroutines" but they are not
** actually called using Gosub and they do not Return. EofA and EofB loop
** until all data is exhausted then jump to the "end" labe. AltB, AeqB,
** and AgtB jump to either L2 or to one of EofA or EofB.
*/
static int multiSelectOrderBy(
Parse *pParse, /* Parsing context */
Select *p, /* The right-most of SELECTs to be coded */
SelectDest *pDest, /* What to do with query results */
char *aff /* If eDest is SRT_Union, the affinity string */
){
int rc = SQLITE_OK; /* Success code from a subroutine */
Select *pPrior; /* Another SELECT immediately to our left */
Vdbe *v; /* Generate code to this VDBE */
int nCol; /* Number of columns in the result set */
ExprList *pOrderBy; /* The ORDER BY clause on p */
int aSetP2[2]; /* Set P2 value of these op to number of columns */
int nSetP2 = 0; /* Number of slots in aSetP2[] used */
SelectDest destA; /* Destination for coroutine A */
SelectDest destB; /* Destination for coroutine B */
int regAddrA;
int regEofA;
int regAddrB;
int regEofB;
int addrSelectA;
int addrSelectB;
int regOutA;
int regOutB;
int addrOutA;
int addrOutB;
int addrEofA;
int addrEofB;
int addrAltB;
int addrAeqB;
int addrAgtB;
int labelCmpr;
int labelEnd;
int j1, j2, j3;
/* Patch up the ORDER BY clause */
pPrior = p->pPrior;
regAddrA = ++pParse->nMem;
regEofA = ++pParse->nMem;
regAddrB = ++pParse->nMem;
regEofB = ++pParse->nMem;
regOutA = ++pParse->nMem;
regOutB = ++pParse->nMem;
sqlite3SelectDestInit(&destA, SRT_Coroutine, regAddrA);
sqlite3SelectDestInit(&destB, SRT_Coroutine, regAddrB);
j1 = sqlite3VdbeAddOp0(v, OP_Goto);
addrSelectA = sqlite3VdbeCurrentAddr(v);
VdbeNoopComment((v, "Begin coroutine for left SELECT"));
sqlite3SelectDestInit(&destA, SRT_Coroutine, 0);
sqlite3Select();
sqlite3VdbeAddOp2(v, OP_Integer, 1, regEofA);
sqlite3VdbeAddOp2(v, OP_Yield, regAddrA);
VdbeNoopComment((v, "End coroutine for left SELECT"));
addrSelectB = sqlite3VdbeCurrentAddr(v);
VdbeNoopComment((v, "Begin coroutine for right SELECT"));
sqlite3SelectDestInit(&destB, SRT_Coroutine, 0);
sqlite3Select();
sqlite3VdbeAddOp2(v, OP_Integer, 1, regEofB);
sqlite3VdbeAddOp2(v, OP_Yield, regAddrB);
VdbeNoopComment((v, "End coroutine for right SELECT"));
VdbeNoopComment((v, "Output routine for A"));
addrOutA = outputSubroutine(pParse, &destA, pDest);
VdbeNoopComment((v, "Output routine for B"));
addrOutB = outputSubroutine(pParse, &destB, pDest);
if( op==TK_EXCEPT || op==TK_INTERSECT ){
addrEofA = iEnd;
}else{
VdbeNoopCommment((v, "eof-A subroutine"));
addrEofA = sqlite3VdbeCurrentAddr(v);
if( op==TK_ALL ){
j2 = sqlite3VdbeAddOp2(v, OP_If, regEofB, labelEnd);
sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB);
sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
sqlite3VdbeAddOp2(v, OP_Goto, 0, j2);
}else{
assert( op==TK_UNION );
sqlite3VdbeAddOp2(v, OP_If, regEofB, labelEnd);
sqlite3ExprCodeMove(pParse, destB.iMem, destA.iMem, destB.nMem);
j2 = sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB);
sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
sqlite3VdbeAddOp2(v, OP_If, regEofB, labelEnd);
sqlite3VdbeAddOp3(v, OP_Compare, destA.iMem, destB.iMem, destB.nMem);
sqlite3VdbeAddOp3(v, OP_Jump, j2, j2+1, j2);
}
}
if( op==TK_INTERSECT ){
addrEofA = iEnd;
}else{
VdbeNoopCommment((v, "eof-B subroutine"));
addrEofA = sqlite3VdbeCurrentAddr(v);
if( op==TK_ALL || op==TK_EXCEPT ){
j2 = sqlite3VdbeAddOp2(v, OP_If, regEofA, labelEnd);
sqlite3VdbeAddOp2(v, OP_Gosub, regOutA, addrOutA);
sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
sqlite3VdbeAddOp2(v, OP_Goto, 0, j2);
}else{
assert( op==TK_UNION );
sqlite3VdbeAddOp2(v, OP_If, regEofA, labelEnd);
sqlite3ExprCodeMove(pParse, destA.iMem, destB.iMem, destA.nMem);
j2 = sqlite3VdbeAddOp2(v, OP_Gosub, regOutA, addrOutA);
sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
sqlite3VdbeAddOp2(v, OP_If, regEofA, labelEnd);
sqlite3VdbeAddOp3(v, OP_Compare, destA.iMem, destB.iMem, destB.nMem);
sqlite3VdbeAddOp3(v, OP_Jump, j2, j2+1, j2);
}
}
VdbeNoopComment((v, "A-lt-B subroutine"));
addrAltB = sqlite3VdbeCurrentAddr(v);
if( op!=TK_INTERSECT ){
sqlite3VdbeAddOp2(v, OP_Gosub, regOutA, addrOutA);
}
addrAeqB = sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
sqlite3VdbeAddOp2(v, OP_Goto, 0, labelCompare);
if( op==TK_ALL ){
addrAeqB = addrAltB;
}else if( op==TK_INTERSECT ){
VdbeNoopComment((v, "A-eq-B subroutine"));
sqlite3VdbeAddOp2(v, OP_Gosub, regOutA, addrOutA);
j2 = sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
sqlite3VdbeAddOp4(v, OP_Compare, destA.iMem, destB.iMem, destA.iMem,
pKeyInfo, P4_KEYINFO_STATIC);
j3 = sqlite3VdbeCurrentAddr(v)+1;
sqlite3VdbeAddOp3(v, OP_Jump, j3, j2, j3);
sqlite3VdbeAddOp2(v, OP_Goto, 0, labelCompare);
}
VdbeNoopComment((v, "A-gt-B subroutine"));
addrAgtB = sqlite3VdbeCurrentAddr(v);
if( op==TK_ALL || op==TK_UNION ){
sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB);
}
sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);
sqlite3VdbeAddOp2(v, OP_Goto, 0, labelCompare);
sqlite3VdbeJumpHere(v, j1);
sqlite3VdbeAddOp2(v, OP_Integer, 0, regEofA);
sqlite3VdbeAddOp2(v, OP_Integer, 0, regEofB);
sqlite3VdbeAddOp2(v, OP_Integer, addrSelectA, regAddrA);
sqlite3VdbeAddOp2(v, OP_Integer, addrSelectB, regAddrB);
sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);
sqlite3VdbeResolve(v, labelCompare);
sqlite3VdbeAddOp4(v, OP_Compare, destA.iMem, destB.iMem, destA.iMem,
pKeyInfo, P4_KEYINFO_HANDOFF);
sqlite3VdbeAddOp3(v, OP_Jump, addrAltB, addrAeqB, addrAgtB);
sqlite3VdbeResolveLabel(v, labelEnd);
}
#endif /***** ########### *****/
#ifndef SQLITE_OMIT_VIEW
/* Forward Declarations */
static void substExprList(sqlite3*, ExprList*, int, ExprList*);
@@ -3472,7 +3823,7 @@ int sqlite3Select(
}
}
sqlite3VdbeAddOp4(v, OP_Compare, iAMem, iBMem, pGroupBy->nExpr,
(char*)pKeyInfo, P4_KEYINFO_STATIC);
(char*)pKeyInfo, P4_KEYINFO);
j1 = sqlite3VdbeCurrentAddr(v);
sqlite3VdbeAddOp3(v, OP_Jump, j1+1, 0, j1+1);
@@ -3485,9 +3836,7 @@ int sqlite3Select(
** and resets the aggregate accumulator registers in preparation
** for the next GROUP BY batch.
*/
for(j=0; j<pGroupBy->nExpr; j++){
sqlite3ExprCodeMove(pParse, iBMem+j, iAMem+j);
}
sqlite3ExprCodeMove(pParse, iBMem, iAMem, pGroupBy->nExpr);
sqlite3VdbeAddOp2(v, OP_Gosub, regOutputRow, addrOutputRow);
VdbeComment((v, "output one row"));
sqlite3VdbeAddOp2(v, OP_IfPos, iAbortFlag, addrEnd);