Re:Sqitch - Sane database change management
by zamalek on Monday August 31, 2015 @11:36AM
(#10147267)
> you are looking at a one-off migration event.
Right, and that's where you roll up your sleeves and describe how to upgrade to that new column; just like you'd handle an out-of-date wire format with C++. No matter how you look at it, you'll always have to manually deal with the most complex upgrade scenarios no matter what you are targeting (RDBMS/CPU/car/washing machine).
The question remains: why are we doing that all the time?
When version 1.2 of a table's DDL adds a new, not nullable column to the version 1.1 definition and there are a billion rows in production, you are looking at a one-off migration event.