Hi,

At April 28, 2004, 10:53, Daniel K. P. Rezende wrote:

> When I migrated from firebird 1.0 to 1.5 I started to have many problemas with LEFT JOIN.
> The same queries I used before the migration doesn´t works
> returning no values or catastrophic failures in DB Express.
> Is there a previous thread about this subject? If not, what
> could be this? Is there any documentation about it?

I thought that it was in the release notes, but apparently not. There
has been some changes in relations to how the FROM clause is
structured.

In example:

FB 1.0:

SELECT
...
FROM Table1
LEFT JOIN Table2 ON Table2.Field1=Table1.Field1,
Table3, Table4

The above statement will generate an error in FB 1.5. Here's how it
should be written for FB 1.5:
SELECT
...
FROM Table1,
Table3,
Table4
LEFT JOIN Table2 ON Table2.Field1=Table1.Field1

Apparently(if my memory serves me well), in the FB 1.0 scenario, there
were chances that the result set was wrong, in some circumstances.
And, it also helped the optimizer to better understand the FROM
clause.

--
Best regards,
Daniel Rail
Senior System Engineer
ACCRA Group Inc. (www.accra.ca)
ACCRA Med Software Inc. (www.filopto.com)