Oracle insert if not exists statement

Question

insert into OPT (email, campaign_id) values(\'mom@cox.net\',100)
where not exists( select * from OPT where (email =\"mom@cox.net\" and campaign_id =100)) ;
         


        

Answer 1

insert into OPT       (email,        campaign_id) 
select 'mom@coxnet' as email, 100 as campaign_id from dual MINUS
select                 email,        campaign_id from OPT;

If there is already a record with mom@cox.net/100 in OPT, the MINUS will subtract this record from the select 'mom@coxnet' as email, 100 as campaign_id from dual record and nothing will be inserted. On the other hand, if there is no such record, the MINUS does not subract anything and the values mom@coxnet/100 will be inserted.

As p.marino has already pointed out, merge is probably the better (and more correct) solution for your problem as it is specifically designed to solve your task.