Benjamin Pflugmann wrote:
>Hi.
>
>On Wed 2002-07-24 at 09:46:03 +0100, [EMAIL PROTECTED] wrote:
>
>
>
>>As I understand it an ANSI92 join is written as;
>>
>>SELECT b.columnA
>>FROM tableB AS b JOIN ON tableC AS c ON b.id = c.id
>>
>>
>
>Ah. Okay. Was not aware that this was new in ANSI92.
>
>
>
>>Whereas the 'old' style would be;
>>
>>SELECT b.columnA
>>FROM tableB AS b, tableC AS c
>>WHERE b.id = c.id
>>
>>Personally I find the former much easier to read though not sure about
>>the practical differences between them when the statements are executed.
>>
>>
>
>AFAICT, there should be no differences on execution speed.
>
>
We tested a lot with JOINS and found out, that the more expressions in
the WHERE clause the slower it gets, this is very obvious of course, but
it is surprisingly true for JOINS too.
We tried to join about 10-15 tables together with LEFT JOIN and the old
','. The processing time differed drastically. We tested this about 6
months ago with 3.23.36, so this may have be untrue now.
BTW the processing time was about <1 second for the new syntax and up to
30 seconds for the old method.
(Tables had about 300.000 - 1.000.000 rows)
Greetings
Ralf
sql sql sql sql sql sql sql sql sql sql sql sql sql
query query query query query query query query query query query
P.S.: Damn filter!
--
Ralf Narozny
SPLENDID Internet GmbH & Co KG
Skandinaviendamm 212, 24109 Kiel, Germany
fon: +49 431 660 97 0, fax: +49 431 660 97 20
mailto:[EMAIL PROTECTED], http://www.splendid.de
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