SELECT *
FROM main_table AS m
INNER JOIN (
SELECT foo_table.id, foo_table.name
FROM foo_table
LEFT OUTER JOIN foo_meta_table
ON foo_table.id = foo_meta_table.id
UNION ALL
SELECT bar_table.id, bar_table.name
FROM bar_table
LEFT OUTER JOIN bar_meta_table
ON bar_table.id = bar_meta_table.id
) AS u
ON m.id = u.id
WHERE m.title = 'hoge'