Finding tables without Primary or Unique Keys (Mysql)

Finding tables without Primary or Unique Keys:


SELECT t.TABLE_SCHEMA,t.TABLE_NAME,ENGINE
FROM information_schema.TABLES t
INNER JOIN information_schema.COLUMNS c
ON t.TABLE_SCHEMA=c.TABLE_SCHEMA
AND t.TABLE_NAME=c.TABLE_NAME
AND t.TABLE_SCHEMA NOT IN ('performance_schema','information_schema','mysql')
GROUP BY t.TABLE_SCHEMA,t.TABLE_NAME
HAVING sum(if(column_key in ('PRI','UNI'), 1,0))=0;





Finding Foreign key constraints:


SELECT referenced_table_name parent, table_name child, constraint_name
FROM information_schema.KEY_COLUMN_USAGE
WHERE referenced_table_name IS NOT NULL
ORDER BY referenced_table_name;