Urgent: Your [placeholder] database’s functionality is at risk

I’ve been getting these emails daily from DigitalOcean:

Our systems have indicated that your MySQL cluster, [placeholder], has tables without primary keys. We have identified that MySQL tables without primary keys can lead to service replication issues that jeopardize performance and availability. If primary keys are not present for database tables exceeding 5,000 rows, data-loss can occur.

We urge you to take the following actions to ensure that your database [placeholder] continues to operate correctly:

1. Review the following product documentation which details the issue and provides clear mitigation strategies for all impacted users.
2. Implement primary keys for all database tables as described in the documentation.

See the full details at the following link: https://www.digitalocean.com/docs/databases/mysql/how-to/create-primary-keys/

We will continue to notify you of this issue until all MySQL tables have primary keys.

I used the following SQL query to find tables without indexes:

SELECT t.*
FROM INFORMATION_SCHEMA.TABLES t
LEFT JOIN INFORMATION_SCHEMA.COLUMNS c ON c.TABLE_NAME = t.TABLE_NAME
	AND c.COLUMN_KEY = 'PRI'
WHERE c.TABLE_SCHEMA IS NULL
	AND TABLE_TYPE NOT IN ('SYSTEM VIEW', 'VIEW', 'CSV');

I found a few tables that didn’t have primary keys, corrected the issue, and now the only remaining tables are:

• performance_schema (lots of tables)
• mysql (general_log and slow_log, which use the CSV engine)

I created a brand new database and did the same query on the new DB and the results on the new DB matched the results on the old DB. Like both queries returned 51 results.