I'd like to discuss different methodes to fasten a whitelist approach for large list (>1000 elements). So far I have been thinking about MySQL or textfiles on the resource side, and simple switch or sort/search algorithms for the implimentation. With such a large list I'm simply wondering if a textfile would be processed faster than MySQL. Once that is settled I'm wondering if both introduce methodes to speed up the access to a single element, namely searchmethodes like binary search.

If you know about other ways to store a list for a whitelist approach let me know.

Selecting a single record or a set of records with some criteria from a text file will be definitely slower than from MySQL with right indexes created, that's no doubt. Do not try to re-invent a bicycle.