Text insert max. size. - Mailing list pgsql-sql

Hi,

I'm doing some planning for storing some xml data and am wondering
what is the maximum amount I could insert with one SQL statement.

For example if I read an xml file off the hard drive and wanted to store
that in a text column what would be the largest file I could insert.
How about a 10 KB file ?

I guess also each programing language may have limitations too.
I this case I'm interested in using PHP.

Thank you kindly.

Regards
Rudi.