On 29.09.2017 04:33, Amit Langote wrote:
So, we should be looking at partconstraintdef only when verbose is true, because that's only when we set it to a valid value. Now, if partconstraintdef is NULL even after verbose is true, that means backend returned that there exists no constraint for that partition, which I thought would be true for a default partition (because the commit that introduced default partitions also introduced "No partition constraint"), but it's really not.For example, \d and \d+ show contradictory outputs for a default partition. create table p (a int) partition by list (a); create table p1 partition of p for values in (1); create table pd partition of p default; \d pd Table "public.pd" Column | Type | Collation | Nullable | Default --------+---------+-----------+----------+--------- a | integer | | | Partition of: p DEFAULT No partition constraint \d+ pd Table "public.pd" Column | Type | Collation | Nullable | Default | Storage | Stats target | Description --------+---------+-----------+----------+---------+---------+--------------+------------- a | integer | | | | plain | | Partition of: p DEFAULT Partition constraint: (NOT ((a IS NOT NULL) AND (a = ANY (ARRAY[1])))) Perhaps, there is no case when "No partition constraint" should be output, but I may be missing something.
Anyhow, we have to protect ourselves from empty output from *pg_get_partition_constraintdef*. And printing *No partition constraint* would be good point to start to examine why we didn't get any constraint definition.
-- Regards, Maksim Milyutin
