first i have to ask what version of ACF are you using. You mention that one of the db fields looks like 32 required and the required part has be confused, that should not be there. The user field is a field in ACF and it stores user ID values. The difference between a single value 32 and something that looks like this a:1:{i:0;s:3:”281″;}) is whether or not the field allows multiple selections of only a single selection. The second value is a field that allows multiple selections and stores an array of user IDs and what you’re seeing is a serialized value. How you search posts based on the value will depend on what type whether or not your searching a field that allows multiple values or not. If you’re searching a field that uses a single value then you can search for just the value, but if it’s one that allows multiple then you need to use something like LIKE '"'.$user_ID.'"'
The shorting problem is going to be a bit more difficult, and that’s also going to depend on what type of user field you’re searching, there’s too many variables at this point to begin helping you sort that part out.
The first thing we have to do is nail down if the field you’re searching allows 1 or multiple values.
