Also watch out for database functionality differences. For example, with a transactional database (mysql is not) you will either want to add $dbh->commit() statements, or turn on autocommit when you set up the database handle, like:

$dbh = DBI->connect($dsn, $user, $password,
          { RaiseError => 1, AutoCommit => 1 });
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In general, if the goal is to do database manipulation without writing any actual SQL, probably the purest implementation I've seen is Class::DBI.