There is no standard schedule. Search for opening times using Google or, if they have it, the bar’s website or Facebook Page. None of this, though, is ever entirely accurate. Some bars are open all day, every day. Some close during siesta between lunch and dinner. Some close on Sunday, others close on Monday or Tuesday. If they say they open at 7 pm, be prepared for them to open at 7:15 pm. It’s just part of traveling in Spain.