#!/usr/bin/perl use strict; use warnings; use Carp; use DBI; my $dbh = DBI->connect("dbi:Pg:dbname=raum;host=127.0.0.1;port=5432", "perl_db", "test",{ RaiseError => 0, AutoCommit => 0}) or croak $DBI::errstr; print "\n Erfolgreich mit Datenbank verbunden \n \n"; if ($ARGV[0]=='update'){        sub update; } elsif ($ARGV[0]=='insert'){        sub insert; } elsif ($ARGV[0]=='delete'){        sub delete; } elsif ($ARGV[0]=='select'){        sub select; } else { print "Falscher Parameter!"; } #####UPDATE###### sub update { my $cmd = 'UPDATE t_personen SET name= ? WHERE id=?; '; my $sth = $dbh->prepare_cached($cm$   or croak "SQL prepare failed '$cmd': " . $dbh->errstr; my $rc = $sth->execute($ARGV[1],$ARGV[2]); $dbh->commit() or die "Failed to save modified data: " . $dbh->errstr; } ##### delete####### . . . .