How can I remove ASCII text from a field when I use it in a query

Question

How can I remove ASCII text from a field when I use it in a query?
I am running a select statement on a table that appears to have ASCII text in some of the fields. If I use these fields in the where statement like the code below nothing returns:
SELECT FIELD1 FROM TABLE1 WHERE FIELD1 IS NULL
But the field looks empty if I do a straight select without the where clause. Additionally, one of the fields has text but appears to be padded out with ASCII text, which I need to strip out before I can use this field in a where or join statement. I have tried using a trim, ltrim, rtrim, to_char, nvl, decode and nothing works. When I use excel to run the same query it looks as if these ASCII fields are boxes.
I have asked our DBA team to see what they can do to prevent these from going into the table, but in the mean time I still need to run this report.
Do you have any suggestions?

Answer 1

Can you provide an example? I've been trying (for
example) "select translate(' test one', ascii(' '),
'X') from dual" with no luck.
Thank you.To replace space, you should query like this:
select translate(' test one', chr(32), 'X') from dual instead of select translate(' test one', ascii(' '), 'X') from dual Thanks,
Dharmesh Patel