use Modern::Perl; return { bug_number => "31626", description => "Add letter id to the message queue table", up => sub { my ($args) = @_; my ($dbh, $out) = @$args{qw(dbh out)}; unless ( column_exists( 'message_queue', 'letter_id' ) ) { $dbh->do(q{ ALTER TABLE message_queue ADD COLUMN `letter_id` int(11) DEFAULT NULL COMMENT 'Foreign key to the letters table' AFTER message_id, ADD CONSTRAINT letter_fk FOREIGN KEY (letter_id) REFERENCES letter(id) ON DELETE SET NULL ON UPDATE CASCADE }); say $out "Added column 'message_queue.letter_id'"; } }, };