RE: JOIN problem

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Thanks, and thanks to Valeriy Kravchuk too.

> Date: Tue, 28 Nov 2006 11:06:22 +0100> From: [email protected]> To: mribb=
[email protected]> CC: [email protected]> Subject: Re: JOIN problem> > Mic=
hael Ribbons wrote:> > Hi, not sure if this is a bug or a feature added wit=
h the changes for nested JOINs, > > this code works fine under 4.0.24, but =
2nd last query fails under 5.0.26.> > JOIN behavior was changed starting wi=
th MySQL 5.0.12 to become> more ANSI compliant, check the "JOIN Syntax" man=
ual page for> "Join Processing Changes in MySQL 5.0.12"> > vhttp://dev.mysq=
l.com/doc/refman/5.0/en/join.html> > > > > Please observe the following sql=
:> [...]> > SELECT ta.* FROM ta, tc LEFT JOIN tb ON tb.tb_id =3D ta.ta_id;>=
 > ERROR 1054 (42S22): Unknown column 'ta.ta_id' in 'on clause'> > * Previo=
usly, the comma operator (,) and JOIN both had the same> precedence, so the=
 join expression t1, t2 JOIN t3 was interpreted> as ((t1, t2) JOIN t3). Now=
 JOIN has higher precedence, so the> expression is interpreted as (t1, (t2 =
JOIN t3)). This change> affects statements that use an ON clause, because t=
hat clause> can refer only to columns in the operands of the join, and the>=
 change in precedence changes interpretation of what those> operands are.> =
> so rewriting the query like this should solve your problem:> > SELECT ta.=
* FROM (ta, tc) LEFT JOIN tb ON tb.tb_id =3D ta.ta_id;> ^ ^> > > -- > Hartm=
ut Holzgraefe, Senior Support Engineer .> MySQL AB, www.mysql.com>=20
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