0005-Add-function-find_param_path_info.patch

From ec2984ab4ea387d5e91fbd354209ff45f114b603 Mon Sep 17 00:00:00 2001
From: Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>
Date: Mon, 6 Feb 2017 12:14:06 +0530
Subject: [PATCH 05/11] Add function find_param_path_info.

The code to search ParamPathInfo for a set of required outer relations in the
list of ParamPathInfos of a given relation is duplicated in
get_*rel_parampathinfo() functions. Separate this code into
find_param_path_info() and call it from get_*rel_parampathinfo() functions.
---
 src/backend/optimizer/util/relnode.c |   46 ++++++++++++++++++++--------------
 1 file changed, 27 insertions(+), 19 deletions(-)

diff --git a/src/backend/optimizer/util/relnode.c b/src/backend/optimizer/util/relnode.c
index 160ed6d..19982dc 100644
--- a/src/backend/optimizer/util/relnode.c
+++ b/src/backend/optimizer/util/relnode.c
@@ -52,6 +52,8 @@ static List *subbuild_joinrel_joinlist(RelOptInfo *joinrel,
 static void set_foreign_rel_properties(RelOptInfo *joinrel,
 						   RelOptInfo *outer_rel, RelOptInfo *inner_rel);
 static void add_join_rel(PlannerInfo *root, RelOptInfo *joinrel);
+extern ParamPathInfo *find_param_path_info(RelOptInfo *rel,
+									  Relids required_outer);
 
 
 /*
@@ -1047,12 +1049,8 @@ get_baserel_parampathinfo(PlannerInfo *root, RelOptInfo *baserel,
 	Assert(!bms_overlap(baserel->relids, required_outer));
 
 	/* If we already have a PPI for this parameterization, just return it */
-	foreach(lc, baserel->ppilist)
-	{
-		ppi = (ParamPathInfo *) lfirst(lc);
-		if (bms_equal(ppi->ppi_req_outer, required_outer))
-			return ppi;
-	}
+	if ((ppi = find_param_path_info(baserel, required_outer)))
+		return ppi;
 
 	/*
 	 * Identify all joinclauses that are movable to this base rel given this
@@ -1289,12 +1287,8 @@ get_joinrel_parampathinfo(PlannerInfo *root, RelOptInfo *joinrel,
 	*restrict_clauses = list_concat(pclauses, *restrict_clauses);
 
 	/* If we already have a PPI for this parameterization, just return it */
-	foreach(lc, joinrel->ppilist)
-	{
-		ppi = (ParamPathInfo *) lfirst(lc);
-		if (bms_equal(ppi->ppi_req_outer, required_outer))
-			return ppi;
-	}
+	if ((ppi = find_param_path_info(joinrel, required_outer)))
+		return ppi;
 
 	/* Estimate the number of rows returned by the parameterized join */
 	rows = get_parameterized_joinrel_size(root, joinrel,
@@ -1333,7 +1327,6 @@ ParamPathInfo *
 get_appendrel_parampathinfo(RelOptInfo *appendrel, Relids required_outer)
 {
 	ParamPathInfo *ppi;
-	ListCell   *lc;
 
 	/* Unparameterized paths have no ParamPathInfo */
 	if (bms_is_empty(required_outer))
@@ -1342,12 +1335,8 @@ get_appendrel_parampathinfo(RelOptInfo *appendrel, Relids required_outer)
 	Assert(!bms_overlap(appendrel->relids, required_outer));
 
 	/* If we already have a PPI for this parameterization, just return it */
-	foreach(lc, appendrel->ppilist)
-	{
-		ppi = (ParamPathInfo *) lfirst(lc);
-		if (bms_equal(ppi->ppi_req_outer, required_outer))
-			return ppi;
-	}
+	if ((ppi = find_param_path_info(appendrel, required_outer)))
+		return ppi;
 
 	/* Else build the ParamPathInfo */
 	ppi = makeNode(ParamPathInfo);
@@ -1358,3 +1347,22 @@ get_appendrel_parampathinfo(RelOptInfo *appendrel, Relids required_outer)
 
 	return ppi;
 }
+
+/*
+ * Returns a ParamPathInfo for outer relations specified by required_outer, if
+ * already available in the given rel. Returns NULL otherwise.
+ */
+ParamPathInfo *
+find_param_path_info(RelOptInfo *rel, Relids required_outer)
+{
+	ListCell   *lc;
+
+	foreach(lc, rel->ppilist)
+	{
+		ParamPathInfo  *ppi = (ParamPathInfo *) lfirst(lc);
+		if (bms_equal(ppi->ppi_req_outer, required_outer))
+			return ppi;
+	}
+
+	return NULL;
+}
-- 
1.7.9.5