MySQL查找没有主键的表

SELECT table_schema, table_name

FROM information_schema.tables tab

WHERE table_schema = '改成自己的数据库名字'

    AND table_name NOT IN (

             SELECT table_name

             FROM information_schema.columns

             WHERE table_schema = '改成自己的数据库名字'

                      AND column_key = 'PRI'

    );