Fix check for child column generation status matching parent.

In commit 8bf6ec3ba, I mistakenly supposed that MergeAttributes'
loop over saved_schema was reprocessing column definitions that
had already been checked earlier: there is a variant syntax for
creating a child partition in which that's not true.  So we need
to duplicate the full check appearing further up.

(Actually, I believe that the "if (restdef->identity)" part is
not reachable, because we reject identity on partitions earlier.
But it seems wise to keep the check, in case that's ever relaxed,
and to keep this code in sync with the other instance.)

Per report from Alexander Lakhin.

Discussion: https://postgr.es/m/4a8200ca-8378-653e-38ed-b2e1f1611aa6@gmail.com

2 files changed, 28 insertions, 0 deletions

diff --git a/src/test/regress/expected/generated.out b/src/test/regress/expected/generated.out
index 11940c851f2..702774d6444 100644
--- a/src/test/regress/expected/generated.out
+++ b/src/test/regress/expected/generated.out
@@ -730,10 +730,26 @@ CREATE TABLE gtest_child PARTITION OF gtest_parent
 CREATE TABLE gtest_child2 PARTITION OF gtest_parent (
     f3 WITH OPTIONS GENERATED ALWAYS AS (f2 * 22) STORED  -- overrides gen expr
 ) FOR VALUES FROM ('2016-08-01') TO ('2016-09-01');
+CREATE TABLE gtest_child3 PARTITION OF gtest_parent (
+    f3 DEFAULT 42  -- error
+) FOR VALUES FROM ('2016-09-01') TO ('2016-10-01');
+ERROR:  column "f3" inherits from generated column but specifies default
+CREATE TABLE gtest_child3 PARTITION OF gtest_parent (
+    f3 WITH OPTIONS GENERATED ALWAYS AS IDENTITY  -- error
+) FOR VALUES FROM ('2016-09-01') TO ('2016-10-01');
+ERROR:  identity columns are not supported on partitions
 CREATE TABLE gtest_child3 (f1 date NOT NULL, f2 bigint, f3 bigint);
 ALTER TABLE gtest_parent ATTACH PARTITION gtest_child3 FOR VALUES FROM ('2016-09-01') TO ('2016-10-01'); -- error
 ERROR:  column "f3" in child table must be a generated column
 DROP TABLE gtest_child3;
+CREATE TABLE gtest_child3 (f1 date NOT NULL, f2 bigint, f3 bigint DEFAULT 42);
+ALTER TABLE gtest_parent ATTACH PARTITION gtest_child3 FOR VALUES FROM ('2016-09-01') TO ('2016-10-01'); -- error
+ERROR:  column "f3" in child table must be a generated column
+DROP TABLE gtest_child3;
+CREATE TABLE gtest_child3 (f1 date NOT NULL, f2 bigint, f3 bigint GENERATED ALWAYS AS IDENTITY);
+ALTER TABLE gtest_parent ATTACH PARTITION gtest_child3 FOR VALUES FROM ('2016-09-01') TO ('2016-10-01'); -- error
+ERROR:  column "f3" in child table must be a generated column
+DROP TABLE gtest_child3;
 CREATE TABLE gtest_child3 (f1 date NOT NULL, f2 bigint, f3 bigint GENERATED ALWAYS AS (f2 * 33) STORED);
 ALTER TABLE gtest_parent ATTACH PARTITION gtest_child3 FOR VALUES FROM ('2016-09-01') TO ('2016-10-01');
 \d gtest_child
diff --git a/src/test/regress/sql/generated.sql b/src/test/regress/sql/generated.sql
index 87ec8421162..36f6bff3483 100644
--- a/src/test/regress/sql/generated.sql
+++ b/src/test/regress/sql/generated.sql
@@ -390,9 +390,21 @@ CREATE TABLE gtest_child PARTITION OF gtest_parent
 CREATE TABLE gtest_child2 PARTITION OF gtest_parent (
     f3 WITH OPTIONS GENERATED ALWAYS AS (f2 * 22) STORED  -- overrides gen expr
 ) FOR VALUES FROM ('2016-08-01') TO ('2016-09-01');
+CREATE TABLE gtest_child3 PARTITION OF gtest_parent (
+    f3 DEFAULT 42  -- error
+) FOR VALUES FROM ('2016-09-01') TO ('2016-10-01');
+CREATE TABLE gtest_child3 PARTITION OF gtest_parent (
+    f3 WITH OPTIONS GENERATED ALWAYS AS IDENTITY  -- error
+) FOR VALUES FROM ('2016-09-01') TO ('2016-10-01');
 CREATE TABLE gtest_child3 (f1 date NOT NULL, f2 bigint, f3 bigint);
 ALTER TABLE gtest_parent ATTACH PARTITION gtest_child3 FOR VALUES FROM ('2016-09-01') TO ('2016-10-01'); -- error
 DROP TABLE gtest_child3;
+CREATE TABLE gtest_child3 (f1 date NOT NULL, f2 bigint, f3 bigint DEFAULT 42);
+ALTER TABLE gtest_parent ATTACH PARTITION gtest_child3 FOR VALUES FROM ('2016-09-01') TO ('2016-10-01'); -- error
+DROP TABLE gtest_child3;
+CREATE TABLE gtest_child3 (f1 date NOT NULL, f2 bigint, f3 bigint GENERATED ALWAYS AS IDENTITY);
+ALTER TABLE gtest_parent ATTACH PARTITION gtest_child3 FOR VALUES FROM ('2016-09-01') TO ('2016-10-01'); -- error
+DROP TABLE gtest_child3;
 CREATE TABLE gtest_child3 (f1 date NOT NULL, f2 bigint, f3 bigint GENERATED ALWAYS AS (f2 * 33) STORED);
 ALTER TABLE gtest_parent ATTACH PARTITION gtest_child3 FOR VALUES FROM ('2016-09-01') TO ('2016-10-01');
 \d gtest_child