Always write a SELECT WHERE query first

Wed Nov 10 2021

Here's a tip a mentor of mine once gave me: if you're ever going to do a SQL UPDATE in production, write a SELECT ... WHERE query first.

Why? If you start typing UPDATE <table> ... and you forget to add the WHERE part or your WHERE conditions are too broad, you're in big trouble.

Instead, first write out your SELECT ... WHERE query, check the results are what you expect them to be and only then go back and modify the first part of your query to be an UPDATE.