Fix code related to partitioning schemes for dropped columns.

The entry in appinfo->translated_vars can be NULL; if so, we must avoid
dereferencing it.

Ashutosh Bapat

Discussion: http://postgr.es/m/CAFjFpReL7+1ien=-21rhjpO3bV7aAm1rQ8XgLVk2csFagSzpZQ@mail.gmail.com

diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c
index 4e565b3c000e509a9dfa6f1e29c1c6f621e4d3be..a6efb4e1d3963dc8d734447985ae1e83e03d7573 100644 (file)
--- a/src/backend/optimizer/path/allpaths.c
+++ b/src/backend/optimizer/path/allpaths.c
@@ -950,6 +950,18 @@ set_append_rel_size(PlannerInfo *root, RelOptInfo *rel,
                                                    attno - 1);
                    int         child_index;
 
+                   /*
+                    * Ignore any column dropped from the parent.
+                    * Corresponding Var won't have any translation. It won't
+                    * have attr_needed information, since it can not be
+                    * referenced in the query.
+                    */
+                   if (var == NULL)
+                   {
+                       Assert(attr_needed == NULL);
+                       continue;
+                   }
+
                    child_index = var->varattno - childrel->min_attr;
                    childrel->attr_needed[child_index] = attr_needed;
                }

diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index d7a084c5b7953eccfe3369c5264349db88224cc5..ee1f10c8e0a343a207f13869a00bb2ec6d26bcf1 100644 (file)
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -3706,6 +3706,13 @@ ALTER TABLE list_parted2 DROP COLUMN b;
 ERROR:  cannot drop column named in partition key
 ALTER TABLE list_parted2 ALTER COLUMN b TYPE text;
 ERROR:  cannot alter type of column named in partition key
+-- dropping non-partition key columns should be allowed on the parent table.
+ALTER TABLE list_parted DROP COLUMN b;
+SELECT * FROM list_parted;
+ a 
+---
+(0 rows)
+
 -- cleanup
 DROP TABLE list_parted, list_parted2, range_parted;
 DROP TABLE fail_def_part;

diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index 339d25b5e56e04624e8324e0d47cc9f20ac45e10..4ae4c2eceea3824138378a1ebf35f9ae50fedef8 100644 (file)
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -2418,6 +2418,10 @@ ALTER TABLE part_2 INHERIT inh_test;
 ALTER TABLE list_parted2 DROP COLUMN b;
 ALTER TABLE list_parted2 ALTER COLUMN b TYPE text;
 
+-- dropping non-partition key columns should be allowed on the parent table.
+ALTER TABLE list_parted DROP COLUMN b;
+SELECT * FROM list_parted;
+
 -- cleanup
 DROP TABLE list_parted, list_parted2, range_parted;
 DROP TABLE fail_def_part;