Model Evolution

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Model Evolution

Chris
Hello,

I just discovered AM a few days ago and I'm finding it very interesting. I've got a question in regards to model evolution. It sounds like all changes are supposed to be implemented as extensions to the existing model. However, I'm having difficulty with the implementation.

I started with a very simple model with one anchor. I added a number of attributes and generated the SQL code. I then experimented with importing data. Now, I found out that I need to historize one of the attributes. So, I historized the attribute in the modeling tool, and generated the SQL. However, the code will not run against the existing model in the database saying there is an error with the attribute table.
Is this expected behavior?

Thanks,
Chris
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Re: Model Evolution

Olle
Yes, this is expected behavior. When you historize an attribute you will add a version as a part of the primary key of the table (probably a date). This attribute cannot be null. You have to drop and re-create the table.

The script won´t drop the table automatically. This will give you a chance to save your data if needed.
Maybe we should make a better error message in the tool that actually explains this… :-)