From Clause

LEFT, RIGHT, and FULL OUTER JOINs are supported, as are LEFT SEMI JOINs and CROSS JOINs using the equal comparison operator, as shown in the following examples:

SELECT a.* FROM a JOIN b ON (a.id = b.id AND a.department = b.department)

SELECT a.val, b.val, c.val FROM a JOIN b ON (a.key = b.key1) JOIN c ON 
(c.key = b.key2)

SELECT a.val, b.val FROM a LEFT OUTER JOIN b ON (a.key=b.key)
  WHERE a.ds='2009-07-07' AND b.ds='2009-07-07'

However, the following syntax fails because of the use of non-equal comparison operators.

SELECT a.* FROM a JOIN b ON (a.id <> b.id)

Spark SQL does not support join syntax in the form of a comma-separated list of tables. The driver, however, overcomes this limitation by translating the SQL into Spark SQL, as shown in the following examples.