System catalogues
Hi all
I have a problem which I'm not sure how to fix. I store my own metadata
about tables and databases in a central admin database. I would like to
combine data from the admin database with data from pg_attribute
for eg:
SELECT distinct a.attname FROM pg_class c, pg_attribute a, pg_type t WHERE
c.relkind = 'r' and c.relname = 'example' and a.attnum > 0 and
a.attrelid = c.oid and a.atttypid = t.oid ORDER BY attname
but where 'example' is a table in another database, not the admin
database. What I would like to do is a join on my admin metadata with the
data in pg_attribute to see where I have no metadata on the field in
question in the admin database. I hope that makes sense!
Is this possible? Has anyone written any sort of documentation on the
system catalogues that I might be able to read?
Thanks a lot guys
Cheers
Zak
Zak McGregor writes:
for eg:
SELECT distinct a.attname FROM pg_class c, pg_attribute a, pg_type t WHERE
c.relkind = 'r' and c.relname = 'example' and a.attnum > 0 and
a.attrelid = c.oid and a.atttypid = t.oid ORDER BY attnamebut where 'example' is a table in another database, not the admin
database. What I would like to do is a join on my admin metadata with the
data in pg_attribute to see where I have no metadata on the field in
question in the admin database. I hope that makes sense!
This seems like the right idea, but you can't make queries that span more
than one database.
Is this possible? Has anyone written any sort of documentation on the
system catalogues that I might be able to read?
In the Developer's Guide on the web site or in your local installation.
--
Peter Eisentraut peter_e@gmx.net http://funkturm.homeip.net/~peter