Subject Re: [firebird-support] Why field alias can not be used in where clause?
Author Jonathan Neve
Glebas wrote:

>Using FB1.52 on Windows:
>select tbl.fld as alias from tbl where alias is null
>complains about 'alias' in 'where' clause:
>'Column does not belong to referenced table'
FB 1.5.2 doesn't support using aliases in the where clause.

>in firebird 2 release notes I found that now field aliases can be used
>in 'order by' and 'group by'. But why 'where' clause is so special?
I agree, it would be nice. Perhaps in a future version.

I suggested that once, but I was told that it would be difficult because
(IIRC) the where clause is evaluated before the fields in the select.

Best regards,
Jonathan Neve
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