first of all, I know that my question is very similar to that one:
MySQL select rows from exactly 7 days ago
the difference is that my dates are stored in the database as a timestamp.
I know that I can use FROM_UNIXTIME to get the date from the timestamp, the thing is, in another answer I read that was very resource consuming (because the timestamp field has to be converted to date in all the records before comparing).
DATE(from_unixtime(timestamp)) = CURRENT_DATE()
Is there any optimized way to do this?