How to check if file is in correct format

Question

Hi,
I want to check if file is in below format via pl/sql
SCE_ YYYYMMDD
and throw an error if not. If
vsFileName:= 'SCE_20080204';
select TO_DATE(SUBSTR(vsFileName, 5, 8), 'YYYYMMDD') - 1 from dual
woudl return 2/3/2008. This is okay
vsFileName:= ''SCE_TEST0204';This is not okay; and would like to trap the error with file name is not correct
Thanks,
VS

Answer 1

Are you just looking for some exception handling?
SQL> ed
Wrote file afiedt.buf
  1  DECLARE
  2    v_filename VARCHAR2(20) := 'SCE_TEST0204';
  3    v_dt       DATE;
  4    v_err      BOOLEAN := FALSE;
  5  BEGIN
  6    BEGIN
  7      v_dt := TO_DATE(SUBSTR(v_filename, 5), 'YYYYMMDD');
  8    EXCEPTION
  9      WHEN OTHERS THEN
10        v_err := TRUE;
11    END;
12    IF v_err THEN
13      DBMS_OUTPUT.PUT_LINE('Filename is incorrect');
14    ELSE
15      DBMS_OUTPUT.PUT_LINE('Filename is OK');
16    END IF;
17* END;
SQL> /
Filename is incorrect
PL/SQL procedure successfully completed.
SQL> ed
Wrote file afiedt.buf
  1  DECLARE
  2    v_filename VARCHAR2(20) := 'SCE_20080204';
  3    v_dt       DATE;
  4    v_err      BOOLEAN := FALSE;
  5  BEGIN
  6    BEGIN
  7      v_dt := TO_DATE(SUBSTR(v_filename, 5), 'YYYYMMDD');
  8    EXCEPTION
  9      WHEN OTHERS THEN
10        v_err := TRUE;
11    END;
12    IF v_err THEN
13      DBMS_OUTPUT.PUT_LINE('Filename is incorrect');
14    ELSE
15      DBMS_OUTPUT.PUT_LINE('Filename is OK');
16    END IF;
17* END;
SQL> /
Filename is OK
PL/SQL procedure successfully completed.
SQL>