"Csaba" <[EMAIL PROTECTED]> wrote in
message news:[EMAIL PROTECTED]
> 1) In the following LEFT JOIN, is it possible to alter
> the query so that there is no w. prefix at the
> beginning of each returned column name:
>
> SELECT w.* FROM Words AS w LEFT JOIN Words as w2
> ON w.Id=w2.Id AND w.Lang=w2.Lang AND w.Rev<w2.Rev
> WHERE w2.Id IS NULL
select * from Words where not exists (
select * from Words w2
where Words.Id = w2.Id and Words.Lang=w2.Lang and Words.Rev<w2.Rev
);
-- or
select * from Words where Rev = (
select max(Rev) from Words w2
where Words.Id = w2.Id and Words.Lang=w2.Lang);
> 3) Which of the following two queries is more efficient (Ie. is
> it better to have the w.Id=527 before or after the WHERE keyword)?
I doubt it makes any difference.
Igor Tandetnik
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