Access to the database itself from your Perl function can be done via
an experimental module DBD::PgSPI
(also available at CPAN
mirror sites). This module makes available a
DBI-compliant database-handle named
$pg_dbh
that can be used to perform queries
with normal DBI syntax.
PL/Perl itself presently provides only one additional Perl command:
elog
level, msgEmit a log or error message. Possible levels are DEBUG, LOG, INFO, NOTICE, WARNING, and ERROR. ERROR raises an error condition: further execution of the function is abandoned, and the current transaction is aborted.