In vfp and T-SQL Left, Right and Full are all outer joins and the typing of "outer" is optional.
Weekend level definition of outer: has nulls if no match available
Pretty sure that is in synch with SQL standards, but perhaps a specific implementation has other rules.


>Is "left join" different from "left inner joint" (http://stackoverflow.com/questions/5706437/whats-the-difference-between-inner-join-left-join-right-join-and-full-join) But http://www.dummies.com/programming/sql/how-to-use-the-sql-outer-join/ writes that: "You can abbreviate the left outer join language as LEFT JOIN because there’s no such thing as a left inner join." That doesn't seem right? And" https://au.pinterest.com/explore/sql-inner-join/
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>>No, it's not the same. You use an inner join which returns records that match
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>>To find the records in table2 that do not have a matching key you need an outer join. The 'is null' clause filters the records that do not have a matching key in Table2 - which was your question
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>>There's a good visual explanation here https://blog.codinghorror.com/a-visual-explanation-of-sql-joins/
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