Question

Autonumber to Integer/Long

3

Good morning, I am doing a data migration and need to change an autonumber to integer or long. When synchronizing the database, it seems like everything gets lost if I try to use integer. I found out that autonumbers are BigInts in the database so long might work (I will try). Is there any documentation telling exactly what the synchronization will do in the database when changing the attribute type from x to y? Even if I find out on my own, it would feel better to have it documented. If it is not, it might be changed in another mendix version and my migration fails because of that (even if it worked with another version)

asked 2019-06-25

Andreas Blaesius

1 answers

Rom van Arendonk · Answer 1 · 2019-06-25

Funny story: back in 2015 we were continuing development on an application which was in production. We had a junior developer test this automatic conversion behavior for every transformation (even ones where it doesn't make sense). The results were quite stunning: data conversions were unpredictable, inconsistent and the database became a mess.

Our recommendation: never use automatic conversions. Always introduce an additional attribute, create a conversion microflow and then remove the original attribute.