What is an OID? What is a TID?” is misleading about the > uniqueness of OIDs.
It does mention the possibility of overflow > (while mentioning that nobody has ever reported it), but it doesn’t > discourage their use as primary keys like the documentation does > in, for example, the following sections: > > http://www.postgresql.org/docs/8.0/static/datatype-oid.html > http://www.postgresql.org/docs/8.0/static/ddl-system-columns.html Wow, that one really needed updating! Here is the new text: ————————————————————————— 4.15) What is an OID? What is a TID? Every row that is created in PostgreSQL gets a unique OID unless created WITHOUT OIDS. OIDs are autotomatically assigned unique 4-byte integers that are unique across the entire installation. However, they overflow at 4 billion, and then the OIDs start being duplicated. PostgreSQL uses OIDs to link its internal system tables together.
