Is there a maximum to the number of else if statements in a create conditional column?

Hi everyone, 

As I know theres a limitation within Power BI to be able to grab data from multilple DBs even though they are in the same SQL Server. 

So to get around this I was thinking of hardcoding some conditional columns, I was hoping to get around the limitation by doing this however I seem to be running into a limit in else if statments before I run into an error saying "This Step results in a query that is not supported by DirectQuery Mode"

Below is a sample of the statement:

= Table.AddColumn(#"Changed Type", "Category", each if [VENDOR] = "ABCD123" then "External" else if [VENDOR] = "EFG123" then "Internal")

Basically the above statement works, until I seem to pass a certain number of else if statements then i get the error.

Is there a max # of else if statements I can use?