Generally, it is a bad idea to run SQL statements - (UPDATE, INSERT, ALTER, DELETE) on your production database. One incorrect statement can have drastic side effects affecting the security and integrity of your data.
But there are situations where different constraints leave you with no choice but to run queries in your production database, if this is the case there are precautions you should take to minimize the potential impact of your queries.
Test Your queries thoroughly
Before Running a query on your production database it is important to test it thoroughly in a development or staging environment. this will allow you to catch any errors or issues before they affect your production data.
Some methods include:
Testing your queries on a mirror database gotten from a snapshot of your production database. Doing this gives you an idea of what to expect and saves you from unwanted errors and side effects.
Testing your "where clause" with a select statement before integrating it into your update, insert, alter or delete statement, Doing this helps you ascertain that you're selecting the correct fields to be mutated.
Getting a peer review of your queries, nothing beats having a second pair of eyes to help fish out those bugs.
Have a rollback plan
Having a rollback plan in place will allow you to quickly and easily undo any changes made by a query in case of an error.
Your rollback plan can involve
Using transactions when making multiple changes, Transactions allow you to make multiple changes in a single atomic operation. if an error occurs during the transaction the entire transaction is rolled back which prevents any partial changes from being made to the data
Having another set of queries prepared and tested that act to undo your initial queries
Be aware of the dependencies
Be aware of the dependencies on the table you're trying to update, and consider the impact on other tables and systems before making any changes to the data.
Avoid live hours
Avoid touching the production database during live hours when users of your application are most active. There will be a lot of user activity going on and your queries might interfere with them in ways you'll be unable to predict.
Running queries on your production database should be avoided, but there are situations where you just have to dive in and do the dirty work. By taking precautions, you can ensure the integrity and security of your production data and minimize the risk of errors or issues when working with your database.