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I want to know if there is any difference in LEFT JOIN and LEFT OUTER JOIN in mySQL. And if there is no difference then why two different ways are there?

Thanks in advance...

user434909
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  • I found a better article: http://www.codeproject.com/Articles/33052/Visual-Representation-of-SQL-Joins, from this answer: http://stackoverflow.com/questions/15425740/are-left-outer-joins-and-left-joins-the-same#answer-15425779 –  Aug 08 '14 at 18:19
  • Possible duplicate of [LEFT JOIN vs. LEFT OUTER JOIN in SQL Server](https://stackoverflow.com/questions/406294/left-join-vs-left-outer-join-in-sql-server) – philipxy Oct 24 '19 at 00:56

1 Answers1

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They are the same, the only reason you would want to put the 'outer' in is for clarity I think, in order to clarify that the first table in the join does not require that it has something to join to in the second table.

This is a good article on wikipedia covering some of this.

Functionally they are the same.

Dave
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