Christian Hammers wrote:
>
> Hello list
>
> While browsing old sources by a former employee I realised that he always
> did comma seperated joins and then a "where"
> FROM
> tablea a, tableb b, tablec c
> WHERE
> a.id=b.id and b.nr=c.nr
> whereas I learned to do
> FROM
> tablea a
> LEFT JOIN table b USING (id)
> LEFT JOIN table c USING (nr)
>
> Is one of the two ways preferred about the other? I like my way as it is
> easier to read and understand but would use anything to gain some speed
> in my 5+ hour selects...
>
> bye,
>
> -christian-
>
He is doing an inner join, you are doing a left join, they (potentialy)
do not produce the same results.
If you have 5 hour selects you are probably missing some vital indexes, or
you are using a long of like '%blah' or "OR"
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