Case Function error "Expecting aggregation but found ..."

[chendan]

I followed the case function instruction case(condiion, value), but it keeps giving me errors.

[leeloo]

I think you're trying to place the custom expression directly in the "summarize" box. You need to place it in a custom column. This article may also help:

Case | Metabase Documentation

A quick note: In v52 and older you can't add a custom column after aggregation unless you have a "group by " clause defined but in v53 you can.