I need to check a text BLOB field in the IBOQuery.OnFilter event, but
the DataSet.FieldByName('MyBlob').AsString is always empty in this event.
But if I add a SUBSTRING on the same BLOB in the query, then
DataSet.FieldByName('MyBlobText').AsString is available in the OnFilter:

SELECT MyBlob
, SUBSTRING( MyBlob FROM 1 FOR 1500) AS MyBlobText
FROM MYTABLE

This solution is not the best. Is there another way to know the
content of a BLOB in the OnFilter.Event ?

Thanks,

Renaud.