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Merge the latest enhancements from trunk.

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FossilOrigin-Name: a7dcf6a79f7e1c5884baee2909a4bf3174ae06d561dae87b390856e573f81b49
This commit is contained in:
drh
2017-05-02 19:45:14 +00:00
parent 6f92c34866 e780764b4e
commit 5034dc673d
13 changed files with 450 additions and 82 deletions
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2
src/btree.c
View File

@@ -8190,6 +8190,7 @@ int sqlite3BtreeInsert(
}else if( loc<0 && pPage->nCell>0 ){
assert( pPage->leaf );
idx = ++pCur->ix;
pCur->curFlags &= ~BTCF_ValidNKey;
}else{
assert( pPage->leaf );
}
@@ -9314,6 +9315,7 @@ static int checkTreePage(
checkAppendMsg(pCheck, "Rowid %lld out of order", info.nKey);
}
maxKey = info.nKey;
keyCanBeEqual = 0; /* Only the first key on the page may ==maxKey */
}
/* Check the content overflow list */

59
src/expr.c
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@@ -1815,6 +1815,65 @@ int sqlite3ExprIsTableConstant(Expr *p, int iCur){
return exprIsConst(p, 3, iCur);
}
/*
** sqlite3WalkExpr() callback used by sqlite3ExprIsConstantOrGroupBy().
*/
static int exprNodeIsConstantOrGroupBy(Walker *pWalker, Expr *pExpr){
ExprList *pGroupBy = pWalker->u.pGroupBy;
int i;
/* Check if pExpr is identical to any GROUP BY term. If so, consider
** it constant. */
for(i=0; i<pGroupBy->nExpr; i++){
Expr *p = pGroupBy->a[i].pExpr;
if( sqlite3ExprCompare(pExpr, p, -1)<2 ){
CollSeq *pColl = sqlite3ExprCollSeq(pWalker->pParse, p);
if( pColl==0 || sqlite3_stricmp("BINARY", pColl->zName)==0 ){
return WRC_Prune;
}
}
}
/* Check if pExpr is a sub-select. If so, consider it variable. */
if( ExprHasProperty(pExpr, EP_xIsSelect) ){
pWalker->eCode = 0;
return WRC_Abort;
}
return exprNodeIsConstant(pWalker, pExpr);
}
/*
** Walk the expression tree passed as the first argument. Return non-zero
** if the expression consists entirely of constants or copies of terms
** in pGroupBy that sort with the BINARY collation sequence.
**
** This routine is used to determine if a term of the HAVING clause can
** be promoted into the WHERE clause. In order for such a promotion to work,
** the value of the HAVING clause term must be the same for all members of
** a "group". The requirement that the GROUP BY term must be BINARY
** assumes that no other collating sequence will have a finer-grained
** grouping than binary. In other words (A=B COLLATE binary) implies
** A=B in every other collating sequence. The requirement that the
** GROUP BY be BINARY is stricter than necessary. It would also work
** to promote HAVING clauses that use the same alternative collating
** sequence as the GROUP BY term, but that is much harder to check,
** alternative collating sequences are uncommon, and this is only an
** optimization, so we take the easy way out and simply require the
** GROUP BY to use the BINARY collating sequence.
*/
int sqlite3ExprIsConstantOrGroupBy(Parse *pParse, Expr *p, ExprList *pGroupBy){
Walker w;
memset(&w, 0, sizeof(w));
w.eCode = 1;
w.xExprCallback = exprNodeIsConstantOrGroupBy;
w.u.pGroupBy = pGroupBy;
w.pParse = pParse;
sqlite3WalkExpr(&w, p);
return w.eCode;
}
/*
** Walk an expression tree. Return non-zero if the expression is constant
** or a function call with constant arguments. Return and 0 if there

115
src/select.c
View File

@@ -4879,6 +4879,103 @@ static void explainSimpleCount(
# define explainSimpleCount(a,b,c)
#endif
/*
** Context object for havingToWhereExprCb().
*/
struct HavingToWhereCtx {
Expr **ppWhere;
ExprList *pGroupBy;
};
/*
** sqlite3WalkExpr() callback used by havingToWhere().
**
** If the node passed to the callback is a TK_AND node, return
** WRC_Continue to tell sqlite3WalkExpr() to iterate through child nodes.
**
** Otherwise, return WRC_Prune. In this case, also check if the
** sub-expression matches the criteria for being moved to the WHERE
** clause. If so, add it to the WHERE clause and replace the sub-expression
** within the HAVING expression with a constant "1".
*/
static int havingToWhereExprCb(Walker *pWalker, Expr *pExpr){
if( pExpr->op!=TK_AND ){
struct HavingToWhereCtx *p = pWalker->u.pHavingCtx;
if( sqlite3ExprIsConstantOrGroupBy(pWalker->pParse, pExpr, p->pGroupBy) ){
sqlite3 *db = pWalker->pParse->db;
Expr *pNew = sqlite3ExprAlloc(db, TK_INTEGER, &sqlite3IntTokens[1], 0);
if( pNew ){
Expr *pWhere = *(p->ppWhere);
SWAP(Expr, *pNew, *pExpr);
pNew = sqlite3ExprAnd(db, pWhere, pNew);
*(p->ppWhere) = pNew;
}
}
return WRC_Prune;
}
return WRC_Continue;
}
/*
** Transfer eligible terms from the HAVING clause of a query, which is
** processed after grouping, to the WHERE clause, which is processed before
** grouping. For example, the query:
**
** SELECT * FROM <tables> WHERE a=? GROUP BY b HAVING b=? AND c=?
**
** can be rewritten as:
**
** SELECT * FROM <tables> WHERE a=? AND b=? GROUP BY b HAVING c=?
**
** A term of the HAVING expression is eligible for transfer if it consists
** entirely of constants and expressions that are also GROUP BY terms that
** use the "BINARY" collation sequence.
*/
static void havingToWhere(
Parse *pParse,
ExprList *pGroupBy,
Expr *pHaving,
Expr **ppWhere
){
struct HavingToWhereCtx sCtx;
Walker sWalker;
sCtx.ppWhere = ppWhere;
sCtx.pGroupBy = pGroupBy;
memset(&sWalker, 0, sizeof(sWalker));
sWalker.pParse = pParse;
sWalker.xExprCallback = havingToWhereExprCb;
sWalker.u.pHavingCtx = &sCtx;
sqlite3WalkExpr(&sWalker, pHaving);
}
/*
** Check to see if the pThis entry of pTabList is a self-join of a prior view.
** If it is, then return the SrcList_item for the prior view. If it is not,
** then return 0.
*/
static struct SrcList_item *isSelfJoinView(
SrcList *pTabList, /* Search for self-joins in this FROM clause */
struct SrcList_item *pThis /* Search for prior reference to this subquery */
){
struct SrcList_item *pItem;
for(pItem = pTabList->a; pItem<pThis; pItem++){
if( pItem->pSelect==0 ) continue;
if( pItem->fg.viaCoroutine ) continue;
if( pItem->zName==0 ) continue;
if( sqlite3_stricmp(pItem->zDatabase, pThis->zDatabase)!=0 ) continue;
if( sqlite3_stricmp(pItem->zName, pThis->zName)!=0 ) continue;
if( sqlite3ExprCompare(pThis->pSelect->pWhere, pItem->pSelect->pWhere, -1) ){
/* The view was modified by some other optimization such as
** pushDownWhereTerms() */
continue;
}
return pItem;
}
return 0;
}
/*
** Generate code for the SELECT statement given in the p argument.
**
@@ -5113,6 +5210,8 @@ int sqlite3Select(
int topAddr;
int onceAddr = 0;
int retAddr;
struct SrcList_item *pPrior;
assert( pItem->addrFillSub==0 );
pItem->regReturn = ++pParse->nMem;
topAddr = sqlite3VdbeAddOp2(v, OP_Integer, 0, pItem->regReturn);
@@ -5126,9 +5225,14 @@ int sqlite3Select(
}else{
VdbeNoopComment((v, "materialize \"%s\"", pItem->pTab->zName));
}
sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor);
explainSetInteger(pItem->iSelectId, (u8)pParse->iNextSelectId);
sqlite3Select(pParse, pSub, &dest);
pPrior = isSelfJoinView(pTabList, pItem);
if( pPrior ){
sqlite3VdbeAddOp2(v, OP_OpenDup, pItem->iCursor, pPrior->iCursor);
}else{
sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor);
explainSetInteger(pItem->iSelectId, (u8)pParse->iNextSelectId);
sqlite3Select(pParse, pSub, &dest);
}
pItem->pTab->nRowLogEst = pSub->nSelectRow;
if( onceAddr ) sqlite3VdbeJumpHere(v, onceAddr);
retAddr = sqlite3VdbeAddOp1(v, OP_Return, pItem->regReturn);
@@ -5347,6 +5451,11 @@ int sqlite3Select(
sqlite3ExprAnalyzeAggList(&sNC, pEList);
sqlite3ExprAnalyzeAggList(&sNC, sSort.pOrderBy);
if( pHaving ){
if( pGroupBy ){
assert( pWhere==p->pWhere );
havingToWhere(pParse, pGroupBy, pHaving, &p->pWhere);
pWhere = p->pWhere;
}
sqlite3ExprAnalyzeAggregates(&sNC, pHaving);
}
sAggInfo.nAccumulator = sAggInfo.nColumn;

2
src/sqlite.h.in
View File

@@ -857,7 +857,7 @@ struct sqlite3_io_methods {
** opcode allows these two values (10 retries and 25 milliseconds of delay)
** to be adjusted. The values are changed for all database connections
** within the same process. The argument is a pointer to an array of two
** integers where the first integer i the new retry count and the second
** integers where the first integer is the new retry count and the second
** integer is the delay. If either integer is negative, then the setting
** is not changed but instead the prior value of that setting is written
** into the array entry, allowing the current retry settings to be

21
src/sqliteInt.h
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@@ -3318,15 +3318,17 @@ struct Walker {
int walkerDepth; /* Number of subqueries */
u8 eCode; /* A small processing code */
union { /* Extra data for callback */
NameContext *pNC; /* Naming context */
int n; /* A counter */
int iCur; /* A cursor number */
SrcList *pSrcList; /* FROM clause */
struct SrcCount *pSrcCount; /* Counting column references */
struct CCurHint *pCCurHint; /* Used by codeCursorHint() */
int *aiCol; /* array of column indexes */
struct IdxCover *pIdxCover; /* Check for index coverage */
struct IdxExprTrans *pIdxTrans; /* Convert indexed expr to column */
NameContext *pNC; /* Naming context */
int n; /* A counter */
int iCur; /* A cursor number */
SrcList *pSrcList; /* FROM clause */
struct SrcCount *pSrcCount; /* Counting column references */
struct CCurHint *pCCurHint; /* Used by codeCursorHint() */
int *aiCol; /* array of column indexes */
struct IdxCover *pIdxCover; /* Check for index coverage */
struct IdxExprTrans *pIdxTrans; /* Convert indexed expr to column */
ExprList *pGroupBy; /* GROUP BY clause */
struct HavingToWhereCtx *pHavingCtx; /* HAVING to WHERE clause ctx */
} u;
};
@@ -3796,6 +3798,7 @@ void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
int sqlite3ExprIsConstant(Expr*);
int sqlite3ExprIsConstantNotJoin(Expr*);
int sqlite3ExprIsConstantOrFunction(Expr*, u8);
int sqlite3ExprIsConstantOrGroupBy(Parse*, Expr*, ExprList*);
int sqlite3ExprIsTableConstant(Expr*,int);
#ifdef SQLITE_ENABLE_CURSOR_HINTS
int sqlite3ExprContainsSubquery(Expr*);

31
src/vdbe.c
View File

@@ -3540,6 +3540,37 @@ open_cursor_set_hints:
break;
}
/* Opcode: OpenDup P1 P2 * * *
**
** Open a new cursor P1 that points to the same ephemeral table as
** cursor P2. The P2 cursor must have been opened by a prior OP_OpenEphemeral
** opcode. Only ephemeral cursors may be duplicated.
**
** Duplicate ephemeral cursors are used for self-joins of materialized views.
*/
case OP_OpenDup: {
VdbeCursor *pOrig; /* The original cursor to be duplicated */
VdbeCursor *pCx; /* The new cursor */
pOrig = p->apCsr[pOp->p2];
assert( pOrig->pBtx!=0 ); /* Only ephemeral cursors can be duplicated */
pCx = allocateCursor(p, pOp->p1, pOrig->nField, -1, CURTYPE_BTREE);
if( pCx==0 ) goto no_mem;
pCx->nullRow = 1;
pCx->isEphemeral = 1;
pCx->pKeyInfo = pOrig->pKeyInfo;
pCx->isTable = pOrig->isTable;
rc = sqlite3BtreeCursor(pOrig->pBtx, MASTER_ROOT, BTREE_WRCSR,
pCx->pKeyInfo, pCx->uc.pCursor);
/* The sqlite3BtreeCursor() routine can only fail for the first cursor
** opened for a database. Since there is already an open cursor when this
** opcode is run, the sqlite3BtreeCursor() cannot fail */
assert( rc==SQLITE_OK );
break;
}
/* Opcode: OpenEphemeral P1 P2 * P4 P5
** Synopsis: nColumn=P2
**

4
src/vdbeaux.c
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@@ -2044,8 +2044,8 @@ void sqlite3VdbeFreeCursor(Vdbe *p, VdbeCursor *pCx){
break;
}
case CURTYPE_BTREE: {
if( pCx->pBtx ){
sqlite3BtreeClose(pCx->pBtx);
if( pCx->isEphemeral ){
if( pCx->pBtx ) sqlite3BtreeClose(pCx->pBtx);
/* The pCx->pCursor will be close automatically, if it exists, by
** the call above. */
}else{