INVALID MONTH ERROR

Question

I have seen a thread on this topic. But my issue is a bit different.
I have a table (suppose A) with a date column (let b B)
There is a view on this table say A_V. This view simply queries the table A.
I have another table C, to which I am inserting record from A_V in a for loop like
FOR i IN (SELECT * FROM A_V)
LOOP
INSERT INTO C(x,y,B)
VALUES( i.x,i.y,nvl(i.B,sysdate) );
END LOOP;
I found invalid month issue in it. I am not sure of the reason. However, do I need apply to_char on i.B or nvl(i.B,sysdate) to give it a specific format. And if so, how would I know what format I should apply.
I was also doing some test plsql developer and found result like this. Can anyone help me understand.
select id,nvl(to_char(DATE_DATA,'dd/MM/yyyy'),to_date('19000101','YYYYMMDD')) from DATA_DUMP
where DATE_DATA is null
result is
1 361725 01-JAN-00
2 800001 01-JAN-00
3 800002 01-JAN-00
4 420068 01-JAN-00
5 442682 01-JAN-00
6 442984 01-JAN-00
7 442340 01-JAN-00
select id,nvl(DATE_DATA,to_date('19000101','YYYYMMDD')) from DATA_DUMP
where DATE_DATA is null
1 361725 1/1/1900
2 800001 1/1/1900
3 800002 1/1/1900
4 420068 1/1/1900
5 442682 1/1/1900
6 442984 1/1/1900
7 442340 1/1/1900
I get similar result with DATA_DATA not null too.
-Deb

Answer 1

p.s. you also don't need to do your insert as single inserts within a cursor loop as this will give you poor performance. It should be done as a single insert... select... statement.
e.g.
SQL> select * from a;
     EMPNO     DEPTNO B
      7369         20 17/12/1980 00:00:00
      7499         30 20/02/1981 00:00:00
      7521         30 22/02/1981 00:00:00
      7566         20 02/04/1981 00:00:00
      7654         30 28/09/1981 00:00:00
      7698         30 01/05/1981 00:00:00
      7782         10 09/06/1981 00:00:00
      7788         20
      7839         10 17/11/1981 00:00:00
      7844         30 08/09/1981 00:00:00
      7876         20
      7900         30 03/12/1981 00:00:00
      7902         20 03/12/1981 00:00:00
      7934         10 23/01/1982 00:00:00
14 rows selected.
SQL> create table c (empno number, deptno number, b date);
Table created.
SQL> insert into c
  2  select empno, deptno, nvl(b,sysdate)
  3  from a;
14 rows created.
SQL> select * from c;
     EMPNO     DEPTNO B
      7369         20 17/12/1980 00:00:00
      7499         30 20/02/1981 00:00:00
      7521         30 22/02/1981 00:00:00
      7566         20 02/04/1981 00:00:00
      7654         30 28/09/1981 00:00:00
      7698         30 01/05/1981 00:00:00
      7782         10 09/06/1981 00:00:00
      7788         20 09/01/2009 15:24:04
      7839         10 17/11/1981 00:00:00
      7844         30 08/09/1981 00:00:00
      7876         20 09/01/2009 15:24:04
      7900         30 03/12/1981 00:00:00
      7902         20 03/12/1981 00:00:00
      7934         10 23/01/1982 00:00:00
14 rows selected.
SQL>