Hacker News new | ask | show | jobs
by ChymeraXYZ 1111 days ago
How do you deal with for example with this:

New column C

C = A + B

Drop A, B

If I just specify the desired state I get data loss...

1 comments

Good migration systems like Django's will have escape hatches.
Yes but then it's no longer declarative, is it?
Is absolute purity a requirement?
I don't mind.