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LEFT JOIN and LEFT OUTER JOIN works exactly the same way. Which means the keyword OUTER has no effect or it is optional.

Why do we include a keyword which has no effect in execution?

informatik01
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Yogesh H Shenoy
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1 Answers1

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It is optional, I always assumed that it was originally there as its more descriptive.

However it doesn't actually mean anything as a join is either inner, left, right or full - so the outer key word can be inferred to be relevant for all but inner joins.