Is it better to create a custom key for lookup (dim) table, if an existing column exist (as string)

[GeorgeFP]

Hi there,
This is a question about data modelling.

I am no expert, but I understand the idea of foreign and primary keys for relationships.

Question - is it necessary or beneficial to create a column with an integer value in the lookup (dim) table as the key even if another column in text (e.g. country) is available to use as a key?

Thanks in advance.
Regards George

[GeorgeFP]

Thank you Denis

[selimovd · Accepted solution]

Hey @GeorgeFP ,

yes, integer is always the best option for the keys.

Like this the performance and also the amount of space in the data model have the best impact.

https://www.sqlbi.com/articles/the-importance-of-star-schemas-in-power-bi/

https://www.sqlbi.com/blog/marco/2017/10/02/why-data-modeling-is-important-in-powerbi/

If you need any help please let me know.
If I answered your question I would be happy if you could mark my post as a solution ✔️ and give it a thumbs up 👍

Best regards
Denis

Blog: WhatTheFact.bi
Follow me: twitter.com/DenSelimovic