A while back, I wrote Careful with That Lock, Eugene about an idea for how to check if a database migration is likely to disturb production. That post came about after having an inspiring chat with a colleague about the advantages of transactional migration scripts and the ability to check the postgres system catalog views before committing a transaction. Over the past few weeks, I’ve been experimenting with this idea to test if I can use it to build valuable safety checks for DDL migration...
