Join Selection Factor

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O'Connell (2005, 5.10) defines this as "[t]he percentage (or fraction, whichever you choose) of records in one file that will be joined with records of another file". This can be calculated when two database tables are to be joined. It is primarily concerned with query optimisation.

[edit] References

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