Notice: Undefined index

[schan]

I did a search for this title and came across this old thread:
https://vborg.vbsupport.ru/showthrea...ndefined+index

The thread simply tells you how to hide those notices. I don't want to hide them but want to understand why I'm getting them. My hunch is that the indexes from the MySQL table is missing for some of the columns in the user table: userid, membergroupid, and so on. Can someone please confirm if this is true? A search via Google came up with some threads that said to use isset(). Well, the error messages relate to the functions file within vBulletin. I don't want to modify the core file(s).

Thanks,
-S