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-rw-r--r--src/backend/optimizer/prep/prepkeyset.c180
1 files changed, 91 insertions, 89 deletions
diff --git a/src/backend/optimizer/prep/prepkeyset.c b/src/backend/optimizer/prep/prepkeyset.c
index 979796ffe24..914779b4f69 100644
--- a/src/backend/optimizer/prep/prepkeyset.c
+++ b/src/backend/optimizer/prep/prepkeyset.c
@@ -15,89 +15,90 @@
/*
* Node_Copy
- * a macro to simplify calling of copyObject on the specified field
+ * a macro to simplify calling of copyObject on the specified field
*/
#define Node_Copy(from, newnode, field) newnode->field = copyObject(from->field)
-bool _use_keyset_query_optimizer = FALSE;
+bool _use_keyset_query_optimizer = FALSE;
-static int inspectOpNode(Expr *expr);
-static int inspectAndNode(Expr *expr);
-static int inspectOrNode(Expr *expr);
-static int TotalExpr;
+static int inspectOpNode(Expr *expr);
+static int inspectAndNode(Expr *expr);
+static int inspectOrNode(Expr *expr);
+static int TotalExpr;
/**********************************************************************
- * This routine transforms query trees with the following form:
- * SELECT a,b, ... FROM one_table WHERE
- * (v1 = const1 AND v2 = const2 [ vn = constn ]) OR
- * (v1 = const3 AND v2 = const4 [ vn = constn ]) OR
- * (v1 = const5 AND v2 = const6 [ vn = constn ]) OR
- * ...
- * [(v1 = constn AND v2 = constn [ vn = constn ])]
+ * This routine transforms query trees with the following form:
+ * SELECT a,b, ... FROM one_table WHERE
+ * (v1 = const1 AND v2 = const2 [ vn = constn ]) OR
+ * (v1 = const3 AND v2 = const4 [ vn = constn ]) OR
+ * (v1 = const5 AND v2 = const6 [ vn = constn ]) OR
+ * ...
+ * [(v1 = constn AND v2 = constn [ vn = constn ])]
*
- * into
+ * into
*
- * SELECT a,b, ... FROM one_table WHERE
- * (v1 = const1 AND v2 = const2 [ vn = constn ]) UNION
- * SELECT a,b, ... FROM one_table WHERE
- * (v1 = const3 AND v2 = const4 [ vn = constn ]) UNION
- * SELECT a,b, ... FROM one_table WHERE
- * (v1 = const5 AND v2 = const6 [ vn = constn ]) UNION
- * ...
- * SELECT a,b, ... FROM one_table WHERE
- * [(v1 = constn AND v2 = constn [ vn = constn ])]
+ * SELECT a,b, ... FROM one_table WHERE
+ * (v1 = const1 AND v2 = const2 [ vn = constn ]) UNION
+ * SELECT a,b, ... FROM one_table WHERE
+ * (v1 = const3 AND v2 = const4 [ vn = constn ]) UNION
+ * SELECT a,b, ... FROM one_table WHERE
+ * (v1 = const5 AND v2 = const6 [ vn = constn ]) UNION
+ * ...
+ * SELECT a,b, ... FROM one_table WHERE
+ * [(v1 = constn AND v2 = constn [ vn = constn ])]
*
*
- * To qualify for transformation the query must not be a sub select,
- * a HAVING, or a GROUP BY. It must be a single table and have KSQO
- * set to 'on'.
+ * To qualify for transformation the query must not be a sub select,
+ * a HAVING, or a GROUP BY. It must be a single table and have KSQO
+ * set to 'on'.
*
- * The primary use of this transformation is to avoid the exponrntial
- * memory consumption of cnfify() and to make use of index access
- * methods.
+ * The primary use of this transformation is to avoid the exponrntial
+ * memory consumption of cnfify() and to make use of index access
+ * methods.
*
- * [email protected] 1998-08-31
+ * [email protected] 1998-08-31
*
- * May want to also prune out duplicate terms.
+ * May want to also prune out duplicate terms.
**********************************************************************/
void
transformKeySetQuery(Query *origNode)
{
- /* Qualify as a key set query candidate */
- if (_use_keyset_query_optimizer == FALSE ||
- origNode->groupClause ||
- origNode->havingQual ||
- origNode->hasAggs ||
- origNode->utilityStmt ||
- origNode->unionClause ||
- origNode->unionall ||
- origNode->hasSubLinks ||
- origNode->commandType != CMD_SELECT)
+ /* Qualify as a key set query candidate */
+ if (_use_keyset_query_optimizer == FALSE ||
+ origNode->groupClause ||
+ origNode->havingQual ||
+ origNode->hasAggs ||
+ origNode->utilityStmt ||
+ origNode->unionClause ||
+ origNode->unionall ||
+ origNode->hasSubLinks ||
+ origNode->commandType != CMD_SELECT)
return;
- /* Qualify single table query */
+ /* Qualify single table query */
if (length(origNode->rtable) != 1)
- return;
-
- /* Sorry about the global, not worth passing around */
- /* 9 expressions seems like a good number. More than 9 */
- /* and it starts to slow down quite a bit */
- TotalExpr = 0;
- /*************************/
- /* Qualify where clause */
- /*************************/
- if ( ! inspectOrNode((Expr*)origNode->qual) || TotalExpr < 9)
return;
- /* Copy essential elements into a union node */
- while (((Expr*)origNode->qual)->opType == OR_EXPR) {
+ /* Sorry about the global, not worth passing around */
+ /* 9 expressions seems like a good number. More than 9 */
+ /* and it starts to slow down quite a bit */
+ TotalExpr = 0;
+ /*************************/
+ /* Qualify where clause */
+ /*************************/
+ if (!inspectOrNode((Expr *) origNode->qual) || TotalExpr < 9)
+ return;
+
+ /* Copy essential elements into a union node */
+ while (((Expr *) origNode->qual)->opType == OR_EXPR)
+ {
Query *unionNode = makeNode(Query);
- /* Pull up Expr = */
- unionNode->qual = lsecond(((Expr*)origNode->qual)->args);
+ /* Pull up Expr = */
+ unionNode->qual = lsecond(((Expr *) origNode->qual)->args);
- /* Pull up balance of tree */
- origNode->qual = lfirst(((Expr*)origNode->qual)->args);
+ /* Pull up balance of tree */
+ origNode->qual = lfirst(((Expr *) origNode->qual)->args);
unionNode->commandType = origNode->commandType;
unionNode->resultRelation = origNode->resultRelation;
@@ -121,37 +122,38 @@ transformKeySetQuery(Query *origNode)
static int
/**********************************************************************
- * Checks for 1 or more OR terms w/ 1 or more AND terms.
- * AND terms must be equal in size.
- * Returns the number of each AND term.
+ * Checks for 1 or more OR terms w/ 1 or more AND terms.
+ * AND terms must be equal in size.
+ * Returns the number of each AND term.
**********************************************************************/
inspectOrNode(Expr *expr)
{
- int rc;
- Expr *firstExpr, *secondExpr;
+ int rc;
+ Expr *firstExpr,
+ *secondExpr;
- if ( ! (expr && nodeTag(expr) == T_Expr && expr->opType == OR_EXPR))
+ if (!(expr && nodeTag(expr) == T_Expr && expr->opType == OR_EXPR))
return 0;
firstExpr = lfirst(expr->args);
secondExpr = lsecond(expr->args);
- if (nodeTag(firstExpr) != T_Expr || nodeTag(secondExpr) != T_Expr)
+ if (nodeTag(firstExpr) != T_Expr || nodeTag(secondExpr) != T_Expr)
return 0;
if (firstExpr->opType == OR_EXPR && secondExpr->opType == AND_EXPR)
{
- if ((rc = inspectOrNode(firstExpr)) == 0)
+ if ((rc = inspectOrNode(firstExpr)) == 0)
return 0;
- return (rc == inspectAndNode(secondExpr)) ? rc : 0;
+ return (rc == inspectAndNode(secondExpr)) ? rc : 0;
}
else if (firstExpr->opType == AND_EXPR && secondExpr->opType == AND_EXPR)
{
- if ((rc = inspectAndNode(firstExpr)) == 0)
+ if ((rc = inspectAndNode(firstExpr)) == 0)
return 0;
-
- return (rc == inspectAndNode(secondExpr)) ? rc : 0;
-
+
+ return (rc == inspectAndNode(secondExpr)) ? rc : 0;
+
}
return 0;
@@ -160,34 +162,33 @@ inspectOrNode(Expr *expr)
static int
/**********************************************************************
- * Check for one or more AND terms. Each sub-term must be a T_Const
- * T_Var expression.
- * Returns the number of AND terms.
+ * Check for one or more AND terms. Each sub-term must be a T_Const
+ * T_Var expression.
+ * Returns the number of AND terms.
**********************************************************************/
inspectAndNode(Expr *expr)
{
- int rc;
- Expr *firstExpr, *secondExpr;
+ int rc;
+ Expr *firstExpr,
+ *secondExpr;
- if ( ! (expr && nodeTag(expr) == T_Expr && expr->opType == AND_EXPR))
+ if (!(expr && nodeTag(expr) == T_Expr && expr->opType == AND_EXPR))
return 0;
firstExpr = lfirst(expr->args);
secondExpr = lsecond(expr->args);
- if (nodeTag(firstExpr) != T_Expr || nodeTag(secondExpr) != T_Expr)
+ if (nodeTag(firstExpr) != T_Expr || nodeTag(secondExpr) != T_Expr)
return 0;
if (firstExpr->opType == AND_EXPR &&
- secondExpr->opType == OP_EXPR && inspectOpNode(secondExpr))
+ secondExpr->opType == OP_EXPR && inspectOpNode(secondExpr))
{
- rc = inspectAndNode(firstExpr);
- return ((rc) ? (rc + 1) : 0); /* Add up the AND nodes */
+ rc = inspectAndNode(firstExpr);
+ return ((rc) ? (rc + 1) : 0); /* Add up the AND nodes */
}
- else if (firstExpr->opType == OP_EXPR && inspectOpNode(firstExpr) &&
- secondExpr->opType == OP_EXPR && inspectOpNode(secondExpr))
- {
+ else if (firstExpr->opType == OP_EXPR && inspectOpNode(firstExpr) &&
+ secondExpr->opType == OP_EXPR && inspectOpNode(secondExpr))
return 1;
- }
return 0;
}
@@ -195,12 +196,13 @@ inspectAndNode(Expr *expr)
static int
/******************************************************************
- * Return TRUE if T_Var = T_Const, else FALSE
- * Actually it does not test for =. Need to do this!
+ * Return TRUE if T_Var = T_Const, else FALSE
+ * Actually it does not test for =. Need to do this!
******************************************************************/
inspectOpNode(Expr *expr)
{
- Expr *firstExpr, *secondExpr;
+ Expr *firstExpr,
+ *secondExpr;
if (nodeTag(expr) != T_Expr || expr->opType != OP_EXPR)
return FALSE;
@@ -209,5 +211,5 @@ inspectOpNode(Expr *expr)
firstExpr = lfirst(expr->args);
secondExpr = lsecond(expr->args);
- return (firstExpr && secondExpr && nodeTag(firstExpr) == T_Var && nodeTag(secondExpr) == T_Const);
+ return (firstExpr && secondExpr && nodeTag(firstExpr) == T_Var && nodeTag(secondExpr) == T_Const);
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-07-09 03:40:53 +0000