OREDERBY to alphabetize dropdowns

[MPearlman]

I created a starter app (based on a template) just to try things out and everything was on one table with multiple sheets.  I had a sheet named "client list" and then another sheet for "projects" and a REF there back to the client list and (it took me a while) but I used ORDERBY to alphabetize with ORDERBY(Workstreams [Client], [Client Name], FALSE)

Now, I have built an app from scratch (with multiple tables) and I can't get the same ORDERBY syntax to work. I have a client list table named "Client" with a "Client Name" column. Then on the "project" table I have a REF column named "Clients". So this should be the code: ORDERBY(Client [Client Name], [Clients], FALSE) but I get "Orderby has invalid inputs". 

If I try and enter the first sheet by clicking on the list of tables/columns in the Expression Assistant, it pulls the name of the "Client" sheet as "Clients" and not "Client" so it doesn't seem to recognize the correct table name. I checked all the tables in Sheets and all the table name fields in the Data section and they are all named "Client".

Is there some hidden file name someplace that is wrong? In trying to get it to work, I thought maybe table and column names all had to be different so I changed the names, but then changed them all back. I also copied the entire project to see if recreating all the sheets during the copy would correct the issue and it did not.

Any idea what the issue is?

[AleksiAlkio · Accepted solution]

When using ORDERBY(), you need to use key column with it. The "Client name" is not your key column in Client table. 

[MPearlman]

Thanks so much! Coding is not my strong suit so this really helped! Then I also realized that the sort-key is on the same table to call to the "client name" column to sort. I had previously called to the "clients" REF column. so the correct code is: ORDERBY(Client [Key], [Client Name], FALSE)

[AleksiAlkio]

You're welcome!