DBD::Informix

I'm having a little trouble using the DBI functions table_info(), column_info(), and primary_key_info() functions which I've never tried using before now. I'm not certain what sort of values I should specify as arguments. For table_info(), it returns a valid statement handle from which I can 'fetch' the records, but it fetches records for every table in the database REGARDLESS of what my arguments are. I guess DBD::Informix doesn't support the filters (as suggested in the DBI documentation). I can live with that. But for column_info() and primary_key_info(), I have NEVER been successful at getting a valid (defined) statement handle back from the function call REGARDLESS of what my arguments are. Can someone provide sample code or otherwise explain what I am doing wrong? Here is the pertinent code I have... use DBI; use strict; my $dbh ->connect( ... ); my $sth = $dbh->primary_key_info('%','oper','crest'); # this returns undef regardless of what my arguments are... my $data = $sth->fetchall_arrayref; # error: $sth is null (not defined)... Any ideas? Mark

Ah. I found in this document http://search.cpan.org/~johnl/DBD-Informix-2003.04/lib/DBD/Informix/Summary.pm where these functions are not implemented. :(( This is unforntunate because our agency uses 3 different databases, and making this app portable among all three will be very difficult at best. But it does say that "The keys/indexes of a table be fetched by querying on the system catalog.", but it gives no further details. What is the logical way to determine the primary keys of a given table using a system catalog? (I'm not sure I even understand what a system catalog is...) Mark