Inserting file content into column

Hello,
 
Is there a built-in function that reads the contents of a (textual) file which could then be inserted into a given
(varchar)column. What I am after is something like:
 
 
insert into cert ( cert_id,...., x509_data ) values ( nextval('seq_cert'), ...., load_file('./ca/mycert.pem') );
 
I need to do that from a DB init SQL script rather then from an application.
 
Thanks you,
Jan Moravec