Hi Jim,

>>When i execute the folowing SQL query, i get the error colomn "WTG"not found.
>>
>>SELECT detail.avr_ari,;
>> iif(Detail.avr_wtg=.t.,'J','N') as WTG;
>>FROM general!detail;
>>WHERE WTG='J'
>>
>>Is this an impossible kind of query, to include an expressionalias in the WHERE Clause ?
>>
>>Any idea's how to solve this ?
>>
>
>Bjorn,
>
>The WHERE clause of SELECT si applied to the source tables, there is no fild named WTG in the source fields. You can change it to;
>
>WHERE Detail.avr_wtg = "J"
>

This will cause a data-type mismatch. If he's testing against the result of the iif(), he's got to use the HAVING clause.