Using Spool to output data to file

Question

I am trying to write some sql scripts to do spooling of data to files automatically on the 1st day of each month. I use the spool command to output to text file but have problems setting the filename to tag with the date stamp.
Script 1 : to get current year and month and then call script 2 to output to file
==================================================================================
set linesize 800
set pagesize 999
set heading off
Remark Get current year and month from database
Remark
variable v_yyyymm number;
declare
begin
Select to_number(to_char(to_date(to_char(sysdate,'DD/MM/YYYY'))-1,'YYYYMM')) INTO :v_yyyymm From dual;
end;
print v_yyyymm
@script2.sql :v_yyyymm
exit
script2.sql : spool to file
============================
spool Monthly\Audit_Trail_&1..txt
SELECT * FROM AUDIT_TRAIL WHERE TO_NUMBER(TO_CHAR(DATESTAMP,'YYYYMM')) = &1;
spool off
Upon execution in Windows environment, it says that unable to create spool file. It seem
that i can't use a bind variable in the Spool Command. Any alternative ways of achieving that ??? I need the file name to be taged with the date stamp ?

Answer 1

Yet another example:
I usually create a ".cmd" file to run a sql script such as the following:
spool j:\DailyMetrics.sql
select 'spool j:\Daily_Metrics_'||to_char(sysdate,'mmddyy')||'.txt' from dual;
select '@j:\DAILY_METRICS;' from dual;
select 'spool off' from dual;
spool off
This, of course, allows me to then run the "j:\DailyMetrics.sql" script which now spools to a file with today's date as part of its filename and calls the reporting script to generate the data, and then spools off.
Obviously, you can put everything in the ".cmd" file and just schedule it to be run each day.
Good luck :)