!4449 当join quals包含placeholdervar时，不重写fulljoin

Merge pull request !4449 from pengjiong/fix_case

src/gausskernel/optimizer/plan/planner.cpp

@@ -1271,6 +1271,24 @@ static inline bool contain_system_column(Node *var_list)
     return result;
 }
 
+static inline bool contain_placeholdervar(Node *var_list)
+{
+    List* vars = pull_var_clause(var_list, PVC_RECURSE_AGGREGATES, PVC_INCLUDE_PLACEHOLDERS);
+    ListCell* lc = NULL;
+    bool result = false;
+
+    foreach (lc, vars) {
+        Node* var = (Node*)lfirst(lc);
+        if (IsA(var, PlaceHolderVar)) {
+            result = true;
+            break;
+        }
+    }
+
+    list_free_ext(vars);
+    return result;
+}
+
 /* --------------------
  * subquery_planner
  *	  Invokes the planner on a subquery.  We recurse to here for each
@@ -1833,6 +1851,10 @@ Plan* subquery_planner(PlannerGlobal* glob, Query* parse, PlannerInfo* parent_ro
                     support_rewrite = false;
                     break;
                 }
+                if (root->parse->jointree != NULL && contain_placeholdervar(root->parse->jointree->quals)) {
+                    support_rewrite = false;
+                    break;
+                }
                 if (!fulljoin_2_left_union_right_anti_support(root->parse)) {
                     support_rewrite = false;
                     break;

src/test/regress/expected/fulljoin_rewrite.out

@@ -144,6 +144,27 @@ select left(alias8.w_zip ,alias8.w_id) as alias10,true alias11,dense_rank() over
 
 drop table fulltest;
 drop table fulltest2;
+CREATE TABLE fj_table0 ( column32 INT , column36 INT ) ;
+SELECT 1 FROM fj_table0 LEFT JOIN ( SELECT 1 column29 FROM fj_table0 FULL JOIN fj_table0 AS alias0 ON FALSE ) AS alias1 ON TRUE WHERE column29 = 1 ;
+ ?column? 
+----------
+(0 rows)
+
+explain (costs off) SELECT 1 FROM fj_table0 LEFT JOIN ( SELECT 1 column29 FROM fj_table0 FULL JOIN fj_table0 AS alias0 ON FALSE ) AS alias1 ON TRUE WHERE column29 = 1 ;
+                      QUERY PLAN                      
+------------------------------------------------------
+ Nested Loop Left Join
+   Filter: ((1) = 1)
+   ->  Seq Scan on fj_table0
+   ->  Materialize
+         ->  Merge Full Join
+               Join Filter: false
+               ->  Seq Scan on fj_table0
+               ->  Materialize
+                     ->  Seq Scan on fj_table0 alias0
+(9 rows)
+
+drop table fj_table0;
 -- contain system column, don't rewrite full join
 explain (costs off) select t1.oid from pg_class t1 full join pg_constraint t2 on t1.relname = t2.conname;
                 QUERY PLAN                

src/test/regress/sql/fulljoin_rewrite.sql

@@ -49,6 +49,10 @@ select left(alias8.w_zip ,alias8.w_id) as alias10,true alias11,dense_rank() over
 
 drop table fulltest;
 drop table fulltest2;
+CREATE TABLE fj_table0 ( column32 INT , column36 INT ) ;
+SELECT 1 FROM fj_table0 LEFT JOIN ( SELECT 1 column29 FROM fj_table0 FULL JOIN fj_table0 AS alias0 ON FALSE ) AS alias1 ON TRUE WHERE column29 = 1 ;
+explain (costs off) SELECT 1 FROM fj_table0 LEFT JOIN ( SELECT 1 column29 FROM fj_table0 FULL JOIN fj_table0 AS alias0 ON FALSE ) AS alias1 ON TRUE WHERE column29 = 1 ;
+drop table fj_table0;
 
 -- contain system column, don't rewrite full join
 explain (costs off) select t1.oid from pg_class t1 full join pg_constraint t2 on t1.relname = t2.conname;