WordPress custom loop filter by meta_key and value with serialize data

by

philosophical opinion, people that store serialized data do not mean it to be used in searches.

If you need to search in that data, you should hook on the save_post hook (or whatever is relevant) and store whatever you need in a different meta in a way that can be used in search.

Side notes:

  1. Searching in meta is not scalable
  2. LIKE have horrible performance, if you get into the point of using it you should ask yourself where did you go wrong 😉