a.pl

#!/usr/bin/env perl

use strict;
use warnings;

use FindBin;
use lib qq($FindBin::Bin/lib);
use Data::Dumper;

# preapare table
# $ sqlite3 user.db 'CREATE TABLE user (id INTEGER PRIMARY KEY AUTOINCREMENT, nickname, t_mod, user_id);'
# $ sqlite3 user.db 'INSERT INTO user (nickname, user_id) VALUES ("issm", 100);'

# preapare table
# $ mysql -e "CREATE TABLE user (nickname TEXT, t_mod TIMESTAMP, user_id INT)" test
# $ mysql -e 'INSERT user (nickname, user_id) VALUES ("issm", 100)' test

        package Your::Model;
        use DBIx::Skinny setup => {
#            dsn => 'dbi:SQLite:dbname=user.db',
            dsn => 'DBI:mysql:database=test',
            username => '',
            password => '',
        };
        1;

        package Your::Model::Schema;
        use DBIx::Skinny::Schema;
    
        install_table user => schema {
            pk 'id';
            columns qw/
                id
                nickname
                user_id
            /;
        };
        1;

package main;

my $row = Your::Model->new;

        print Data::Dumper->Dump([\$row]);

$row->update(
    'user',
    {nickname => 'issm', t_mod => time()},
    {user_idx => 9}, # ワザとミス．ホントは user_id
);