exporting oracle data to csv

What is the best way to export oracle dat to a coma delimited csv file? I like to be able to schedule this and each extract should contains a prefix as:
ERA_[date/time].csv. I want to use this text file to import into one of our application which only read text delimited file. TIA.

Any suggestion or tools that I need would be really helpful. As of today, I am thinking of doing the following but not sure how to get the date/time to the file name.

set termout off
set hea off
set pagesize 0

spool c:\whatever.csv

select a.a||','||a.b||','||a.c
from a
where a.a="whatever";

spool off

Try this:

Code:

---

set termout off
set hea off
set pagesize 0
col crdt new_value today
select to_char(sysdate,'YYYYMMDD') crdt from dual;
spool c:\whatever_&&today..csv

select a.a||','||a.b||','||a.c
from a
where a.a="whatever";

spool off

---

;)

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