IIF in Access is virtually identical to IF in MySQL.
You should be able to just change
IIF to
IF
You can't use [....] with MySQL. Use `...` instead (those are backticks, the character on same keyboard key as the ~ tilde)
Except you didn't need the [...] in Access and you don't need backticks in MySQL, either.
And you should use apostrophes instead of quotes. MySQL will take either, but quotes are not ANSI compliant.
Code:
SELECT If( Network_1=-1,'Net-1',
If(Network_2=-1,'Net-2',
If(Network_3=-1,'Net-3','')
)
) AS Network
But your ID #4 would mean a different approach, completely.