Re: [BUGS] BUG #14825: enum type: unsafe use?

balazs(at)obiserver(dot)hu writes:
> PostgreSQL version: 10beta4

> testdb=# begin;
> BEGIN
> testdb=# create type enumtype as enum ('v1', 'v2');
> CREATE TYPE
> testdb=# alter type enumtype owner to testrole;
> ALTER TYPE
> testdb=# create table testtable (enumcolumn enumtype not null default 'v1');
> ERROR: unsafe use of new value "v1" of enum type enumtype
> HINT: New enum values must be committed before they can be used.

Hmm, that's pretty annoying. It's happening because check_safe_enum_use
insists that the enum's pg_type entry not be updated-in-transaction.
We thought that the new rules instituted by 15bc038f9 would be generally
more convenient to use than the old ones --- but this example shows
that, for example, pg_dump scripts involving enums often could not
be restored inside a single transaction.

I'm not sure if that qualifies as a stop-ship problem, but it ain't
good, for sure. We need to look at whether we should revert 15bc038f9
or somehow revise its rules.

regards, tom lane