[Impact123]

Like ecca said, threaded queries are the best you can do, although i have some suggestions.
It's important that you don't pass clientindexes to asynchronous callbacks like this one.
Either use getclientserial/getclientfromserial; getclientuserid/getclientofuserid or fetch the steamid in the callback and find the client with the steamid.
If you only want to check if an row with this steamid exists i guess something like this is faster.

Spoiler

PHP Code:

SELECT COUNT(*) FROM  viplist WHERE steamid = 'xyz' LIMIT 1 


Yours sincerey
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