Referring to the posts below,

https://www.outsystems.com/forums/discussion/33857/how-to-use-composite-key/

https://www.outsystems.com/forums/discussion/23087/external-table-with-composite-keys/

What's the difference between a true composite key and the ones suggested in the links above (that is using unique indexes to implement a composite keys?

Hi,

I think the difference is an index can either be unique or not, and a composite key is always unique.

Do you experience a problem with defining a unique index? 

Regards,

Daniel

Thank you Daniël for your input. No, i did not face a problem with defining a unique index. It is just that i came from the background of having a composite key and haven't tried using a unique index approach.