Thread: pg_class and enum types
I was wondering why there is no pg_class record for the enum types. Do we treat the enum types differently? -- Regards, Gevik
On Sun, May 24, 2009 at 4:37 PM, Gevik Babakhani <pgdev@xs4all.nl> wrote: > I was wondering why there is no pg_class record for the enum types. Do we > treat the enum types differently? Because types are stored in pg_type, not pg_class? ...Robert
Robert Haas wrote: > On Sun, May 24, 2009 at 4:37 PM, Gevik Babakhani <pgdev@xs4all.nl> wrote: > >> I was wondering why there is no pg_class record for the enum types. Do we >> treat the enum types differently? >> > > Because types are stored in pg_type, not pg_class? > > ...Robert > That is certainly not true.... check the following... create type test_type as (field1 integer,field2 varchar ); select * from pg_class where relname='test_type' -- Regards, Gevik
Gevik Babakhani wrote: > I was wondering why there is no pg_class record for the enum types. Do > we treat the enum types differently? > Why do you think we should? What would the record look like? cheers andrew
Gevik Babakhani wrote: > Robert Haas wrote: >> On Sun, May 24, 2009 at 4:37 PM, Gevik Babakhani <pgdev@xs4all.nl> >> wrote: >> >>> I was wondering why there is no pg_class record for the enum types. >>> Do we >>> treat the enum types differently? >>> >> >> Because types are stored in pg_type, not pg_class? >> >> ...Robert >> > That is certainly not true.... check the following... > > create type test_type as > ( > field1 integer, > field2 varchar > ); > > select * from pg_class where relname='test_type' It's not so much that enum types are handled specially, but that composite types are. :-) There is no pg_class entry for int either. cheers andrew
Andrew Dunstan wrote: > > > Gevik Babakhani wrote: >> I was wondering why there is no pg_class record for the enum types. >> Do we treat the enum types differently? >> > > Why do you think we should? What would the record look like? > > cheers > > andrew I am not implying whether we should or we should not. I was just looking for the logic behind it. Re-reading what I just wrote with your reply gives me hint. Thanx. -- Regards, Gevik
Andrew Dunstan <andrew@dunslane.net> writes:
> Gevik Babakhani wrote:
>> select * from pg_class where relname='test_type'
> It's not so much that enum types are handled specially, but that
> composite types are. :-)
Relations (tables) have always had both pg_class and pg_type entries.
The pg_class entry denotes the relation proper, the pg_type entry
denotes the relation's rowtype.
Composite types have the same two entries, there's just a different
notion of which one is primary.
(The reason a composite type has to have a pg_class entry is that
it has pg_attribute entries, and those have to have something in
pg_class for their attrelid to link to.)
regards, tom lane
Tom Lane wrote: > Andrew Dunstan <andrew@dunslane.net> writes: > >> Gevik Babakhani wrote: >> >>> select * from pg_class where relname='test_type' >>> > > >> It's not so much that enum types are handled specially, but that >> composite types are. :-) >> > > Relations (tables) have always had both pg_class and pg_type entries. > The pg_class entry denotes the relation proper, the pg_type entry > denotes the relation's rowtype. > > Composite types have the same two entries, there's just a different > notion of which one is primary. > > (The reason a composite type has to have a pg_class entry is that > it has pg_attribute entries, and those have to have something in > pg_class for their attrelid to link to.) > > regards, tom lane > > Thank you :) -- Regards, Gevik