Is LEFT JOIN same as LEFT OUTER JOIN in Hive like RDBMS server

Question

As per the reference provided here, there is no difference between LEFT JOIN and LEFT OUTER JOIN in RDBMS server, except the point that term 'OUTER' is mentioned explicitly as discussed in the below post: LEFT JOIN vs. LEFT OUTER JOIN in SQL Server

Can someone confirm if any way Apache HIVE has changed the semantics of LEFT JOIN or LEFT OUTER JOIN compared to SQL support in RDBMS server?

@DuduMarkovitz, Hi, I am planning to use hive's left join concept. I just want to make sure my understanding is proper. — Adarsh Thimmappa, Jul 02 '17 at 14:27
Strange question :-) It's the same standard LEFT JOIN you are familiar with — David דודו Markovitz, Jul 02 '17 at 14:53
What did your research re Hive suggest? Or googling variants of good titles? — philipxy, Jul 02 '17 at 18:20

score 0 · Answer 1 · answered Apr 26 '18 at 19:45

I believe Hive did change the semantics on LEFT JOINs between one of their older versions, where it only accepted 'LEFT OUTER JOIN' for defining left joins, and the use of 'LEFT JOIN' (w/o the Outer keyword) would result in a Hive execution error. The word 'Outer' was not optional like it is in other RDBMS. That situation appears to have changed.

Is LEFT JOIN same as LEFT OUTER JOIN in Hive like RDBMS server

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