move data with migration

rubyonrails-talk
1

Hi all,

I have to change my database structure for a new release.

I can change the database structure with migrations but I also want to move the data from the old structure to the new structure. Is this best done via a migration (if possible)?

Thanks Stijn

2

A migration is probably the best way to approach this; you'll be moving your data programmatically as well as creating the new structure. If possible, your 'down' method could put it all back the way it was as well.

I did this recently, and following the create for the new tables, there were a series of data steps within the migration to move data from the old structure to the new. I cloned my live data to my dev envt to make sure I handled all the existing cases. Then test, test, test.