examine this information is to execute queries such as:

<programlisting>

SELECT relname, age(relfrozenxid) FROM pg_class WHERE relkind IN ('r', 'm');

SELECT c.oid::regclass as table_name,

greatest(age(c.relfrozenxid),age(t.relfrozenxid)) as age

FROM pg_class c

LEFT JOIN pg_class t ON c.reltoastrelid = t.oid

WHERE c.relkind IN ('r', 'm');

SELECT datname, age(datfrozenxid) FROM pg_database;

</programlisting>