[thelist] SQL question

Steve Lewis slewis at macrovista.net
Tue Dec 10 17:41:01 CST 2002

Carl J Meyer wrote:
> So my (possibly stupid) question is: why use the JOIN keyword?  What's
So long as you perform inner joins you can probably get away with that
syntax.  I personally consider that a bad habit however.

Because outer joins are NOT associative (A=B does not imply B=A) the
order in which tables are joined directly affects which rows are
included in the result set.  The syntax you are using can generate
erroneous or ambiguous result sets because specifying joins in the WHERE
clause precludes specifically ordering them.


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