619c619,627
<             my ($constraint) = $dbh->selectrow_array("select rcsrc from pg_relcheck where rcname = '${table}_$col_name'");
---
>             # Note: as of PostgreSQL 7.3 pg_relcheck has been replaced
>             # by pg_constraint. To maintain compatibility, check whether
>             # pg_relcheck exists and execute the appropriate query.
> 
>             my ($pre73) = $dbh->selectrow_array("SELECT 1 FROM pg_class WHERE relname='pg_relcheck'") || 0;
>             my $con_query = $pre73 
>              ? "SELECT rcsrc FROM pg_relcheck WHERE rcname = '${table}_$col_name'"
>              : "SELECT consrc FROM pg_catalog.pg_constraint WHERE contype = 'c' AND conname = '${table}_$col_name'";
>             my ($constraint) = $dbh->selectrow_array($con_query);