Converting POSTGRESQL timestamp to UNIX timestamp

Hi

I have a field of type timestamp in my database but when I retrieve it I
want to convert it to its unix timetamp value because I need to compare 2
tables by their timestamp value.

Any ideas how to convert PostgreSQL timestamp to Unix timestamp???

Thanks

Richie

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Richie Duggan
Computer Science IV
University College Cork
Eamil : dugganr@student.cs.ucc.ie   richie_dug@yahoo.com
Homepage : http://student.cs.ucc.ie/01/dugganr/index.html