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

1
votes

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?

1
sqljoinhiveleft-joinhiveql
Why are you asking this? - David דודו Markovitz
@DuduMarkovitz, Hi, I am planning to use hive's left join concept. I just want to make sure my understanding is proper. - Adarsh Thimmappa
Strange question :-) It's the same standard LEFT JOIN you are familiar with - David דודו Markovitz
What did your research re Hive suggest? Or googling variants of good titles? - philipxy

1 Answers

0
votes

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.