Tries to find match up the rows from the primary table to rows in the second desk. If it can’t locate a match, it will eventually return the columns from the primary desk and go away the columns from the second desk blank (null). (NB: In exercise the query optimiser https://praxiskelowna45556.theobloggers.com/42979551/helping-the-others-realize-the-advantages-of-how-to-join-outlaw-motorcycle-club-book