sql - Select AS not working in interbase -

works

select payeeid, extract(weekday checkdate) dow,  (bankcleared - checkdate) datediff   master   (bankcleared not null)   order payeeid, dow, datediff   

adding datediff where - not work

select payeeid, extract(weekday checkdate) dow,  (bankcleared - checkdate) datediff   master   (bankcleared not null)  , (datediff >= 1)   order payeeid, dow, datediff   

you can use column aliases in group by, order by, or having clauses.

standard sql doesn't allow refer column alias in clause. restriction imposed because when code executed, column value may not yet determined.

try this

select payeeid, extract(weekday checkdate) dow,  (bankcleared - checkdate) datediff master (bankcleared not null) , ((bankcleared - checkdate)>= 1) order payeeid, dow, datediff  

for more info go through these links

can use alias in clause in mysql?

unknown column in clause