Find all mysql tables with no primary key. Used to migrate old databases into Digital Ocean managed MySQL.

find-no-primary-key.sql

SELECT table_schema ,table_name FROM information_schema.columns 
WHERE table_schema <> 'sys' AND table_schema <> 'information_schema' AND table_schema <> 'mysql' AND table_schema <> 'performance_schema' 
GROUP BY table_schema ,table_name 
HAVING sum(if (column_key in ('PRI', 'UNI'), 1, 0)) = 0;