On 15/11/2009 5:04 AM, Merlin Moncure wrote: > On Sat, Nov 14, 2009 at 6:01 AM, Craig Ringer > <craig@xxxxxxxxxxxxxxxxxxxxx> wrote: >> On 14/11/2009 6:12 PM, Garry Saddington wrote: >>> How could I list all the tables in a database that do not contain any data? >>> I have looked at reltuples but can't quite work out how to use it, any >>> pointers would be much apreciated. >> >> Define "empty". In a MVCC database, it's harder than you'd think. > If all you care about is if a table has no rows visible to the > current transaction, wouldn't: > select coalesce((select 1 from the_table limit 1), 0)::bool as not_empty; > > be an efficient way to do it (hooking into your idea to get the list > of tables to check above)? Yep. You could wrap something like that up in a PL/PgSQL function that looped over the list of table names obtained from pg_class (with schema names from pg_namespace) and EXECUTEd a query built for each one. -- Craig Ringer -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
