In inheritance, child column's pg_attribute.attislocal flag not getting updated, if it is inherited using ALTER TABLE <child> INHERIT <parent>.
Due to this, if we try to drop column(s) from parent table, which are not getting drop from child. Attached herewith is quick patch fixing this issue.
----------------------Demonstration: ---------------------- CREATE TABLE p1 (a int , b int, c int, d int);
CREATE TABLE c1 () inherits (p1);CREATE TABLE c2 (a int , b int, c int, d int);
--Drop parent's column ALTER TABLE p1 DROP COLUMN b; ALTER TABLE p1 DROP COLUMN c; ALTER TABLE p1 DROP COLUMN d;
postgres=# \d p1 Table "public.p1" Column | Type | Modifiers --------+---------+----------- a | integer | Number of child tables: 2 (Use \d+ to list them.)
postgres=# \d c1 Table "public.c1" Column | Type | Modifiers --------+---------+----------- a | integer | Inherits: p1
postgres=# \d c2 Table "public.c2" Column | Type | Modifiers --------+---------+----------- a | integer | b | integer | c | integer | d | integer | Inherits: p1
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Seems like you missed following command in the demonstration test:
ALTER TABLE c2 INHERIT p1;
You can see columns are not dropped from child c2 table, which we have inherited using ALTER command.
I took a quick look at this and did some testing. Patch looks good to me.
ALTER TABLE INHERIT missing the attislocal = false check.
