Hi,

Helens solution with a shadow column works fine, or course :)

My approach would (in Delphi, never written an UDF myself) look something
like:

function MyUDF(var Value: string): Integer;
begin
Result := StrToIntDef(Value, -MaxInt);
end;

in case of error, it would return -MaxInt, the 'break out' value for the
query.

select * from mytable where myudf(column) > -21... something...

Martijn Tonies
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Upscene Productions
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Thanks Helen&Martin..

Helen,
That was a nice solution.
But is it good to do something like this with 10millions of records?
Or is it a design error that I've done with the table?

Martin, can you please give some tips on how that udf would be like?