MySQL Relationships (JOIN explained)

The visual diagrams still confuse me after so many years and I always forget…so here it is:

INNER JOIN gets all records from one table that have some related entry in a second table

LEFT JOIN gets all records from the LEFT linked table but if you have selected some columns from the RIGHT table, if there is no related records, these columns will contain NULL

RIGHT JOIN is like the above but gets all records in the RIGHT table

FULL JOIN gets all records from both tables and puts NULL in the columns where related records do not exist in the opposite table

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