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Ensure the functions that appear to be constant are not factored out of

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expression that originate on the right-hand side of a LEFT JOIN.
Ticket [6710d2f7a13a2997]

FossilOrigin-Name: 500c9152daaf11cf69d778aa8592175f6088337c6667c59af6df3a24cd81eb0e
This commit is contained in:
drh
2019-08-17 17:07:15 +00:00
parent cc3f3d1f05
commit 9e9a67adb0
4 changed files with 36 additions and 8 deletions
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13
src/expr.c
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@@ -3994,10 +3994,23 @@ expr_code_doover:
break;
}
/* TK_IF_NULL_ROW Expr nodes are inserted ahead of expressions
** that derive from the right-hand table of a LEFT JOIN. The
** Expr.iTable value is the table number for the right-hand table.
** The expression is only evaluated if that table is not currently
** on a LEFT JOIN NULL row.
*/
case TK_IF_NULL_ROW: {
int addrINR;
u8 okConstFactor = pParse->okConstFactor;
addrINR = sqlite3VdbeAddOp1(v, OP_IfNullRow, pExpr->iTable);
/* Temporarily disable factoring of constant expressions, since
** even though expressions may appear to be constant, they are not
** really constant because they originate from the right-hand side
** of a LEFT JOIN. */
pParse->okConstFactor = 0;
inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
pParse->okConstFactor = okConstFactor;
sqlite3VdbeJumpHere(v, addrINR);
sqlite3VdbeChangeP3(v, addrINR, inReg);
break;