Re: [PATCH] Add pg_get_table_ddl() to reconstruct CREATE TABLE statements

Hello!

I did some basic testing with the new functions, and found a few bugs:

1. Seems like check constraints on partitions are ignored:

CREATE TABLE p (id int, val int) PARTITION BY RANGE (id);
CREATE TABLE p_child PARTITION OF p (CONSTRAINT chk_inline CHECK (val > 0))
FOR VALUES FROM (0) TO (100);
SELECT * FROM pg_get_table_ddl('p_child', 'owner','false');

2. inherited stored generated columns can't be replayed:

CREATE TABLE par_s (
id int,
g int GENERATED ALWAYS AS (id * 2) STORED
);
CREATE TABLE ch_s () INHERITS (par_s);
SELECT * FROM pg_get_table_ddl('ch_s', 'owner','false');
-- CREATE TABLE public.ch_s () INHERITS (public.par_s);
-- ALTER TABLE public.ch_s ALTER COLUMN g SET DEFAULT (id * 2);

Dropping ch_s, executing the returned statements:

ERROR: column "g" of relation "ch_s" is a generated column
HINT: Use ALTER TABLE ... ALTER COLUMN ... SET EXPRESSION instead.

3. named not null constraints can't be replayed:

CREATE TABLE t (a int CONSTRAINT my_nn NOT NULL);
SELECT * FROM pg_get_table_ddl('t'::regclass,'owner','false');
-- CREATE TABLE public.t ( a integer NOT NULL);
-- ALTER TABLE public.t ADD CONSTRAINT my_nn NOT NULL a;

Dropping t, executing the statements:

ERROR: cannot create not-null constraint "my_nn" on column "a" of table "t"
DETAIL: A not-null constraint named "t_a_not_null" already exists for
this column.