to_char not working , || is working with join query
NehaRKMar 22 2013 — edited Mar 22 2013Hi,
I have two tables : oa_membership_dtl(in this created_by field is varchar2(200 byte) ,oa_partner_usr_dtl(in this table partner_userid is number(8,0)
i need to do join on above fields.
I am using following two queries:
select * from oa_membership_dtl membership
join oa_partner_usr_dtl partner_user
on to_char(partner_user.partner_userid,'9999')=membership.created_by
select * from oa_membership_dtl membership
join oa_partner_usr_dtl partner_user
on rtrim(ltrim(partner_user.partner_userid||' '))=rtrim(ltrim(membership.created_by))
by using first data is not fetched but 2nd is working fine , i am getting the matched records using 2nd query.
question is why its is so? whats the diff between to_char and || symbol???