The following bug has been logged online:
Bug reference: 4363
Logged by: Dan Boeriu
Email address: dan.boeriu@roost.com
PostgreSQL version: 8.3.3
Operating system: Redhat Linux
Description: ts_query bug
Details:
In 8.3.3
select to_tsquery('') is null returns false
and
select to_tsquery('') = to_tsquery('')
return false too.
I think that the latter is wrong.