Re: Joins

Russell Shaw wrote:
> Hi,
> I'm trying to get a list of all the rows in the Parts table, with
> the integer indexes of man_id, case_id, and desc_id, replaced with text
> from their respective tables. In the Parts table, any of man_id, case_id,
> and desc_id may be absent:

Something like that? :^)

SELECT * FROM parts LEFT OUTER JOIN manufacturers USING (man_id) LEFT OUTER JOIN cases USING
(case_id) LEFT OUTER JOIN descriptions USING (desc_id);

[...]

> Is this right? :
>
> SELECT part, manufacturer, case, description
> FROM parts LEFT OUTER JOIN manufacturers, cases, descriptions
> NATURAL

Hm, don't know if that syntax is correct, but LEFT OUTER JOIN is indeed what you want.
But I don't recomment NATURAL as there may be columns with the same name which you don't want to
join on. I suggest always specify "USING (fieldname)" or "ON (tab1.col1=tab2.col2)".
You can also specify whole subqueries in the ON (...) part.

HTH
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