Join selection factor


Within computing, author O'Connell defines join selection factor as "[t]he percentage (or fraction) of records in one file that will be joined with records of another file".[1] This can be calculated when two database tables are to be joined. It is primarily concerned with query optimisation.


  1. ^ O'Connell, S. (2005) Advanced Databases Course Notes, Southampton, University of Southampton, section 5.10