JOIN is used to combine rows from two or more tables together. Hive supports common
JOIN operations such as what's in the RDBMS, for example,
LEFT OUTER JOIN,
RIGHT OUTER JOIN,
FULL OUTER JOIN, and
CROSS JOIN. However, Hive only supports equal
JOIN instead of unequal
JOIN, because unequal
JOIN is difficult to be converted to MapReduce jobs.
INNER JOIN in Hive uses
JOIN keywords, which return rows meeting the
JOIN conditions from both left and right tables. The
INNER JOIN keyword can also be omitted by comma-separated table names since Hive 0.13.0. See the following examples to show various inner
JOIN statements in Hive:
jdbc:hive2://> CREATE TABLE IF NOT EXISTS employee_hr ...