To handle exception in insert query

Question

Hi ,
I am trying it insert certain records from another table A to temp table B, while doing insert i am having exception of unique constraint in table B how can i check which record is throwing exception while inserting in table A
for eg:
insert into A
select * from B;
i need to handle exception in which record of B i am getting unique constraint error

Answer 1

Hi,
If you add an error logging clause (with keywords LOG ERRORS), then you can insert a row into another table for each row that can't be inserted according to your INSERT statement.
To query table A to see which ids already exist in table B, you can say
SELECT  *
FROM    a
WHERE   a_id  IN (
                      SELECT  b_id
                      FROM    b
where b.b_id is the unique key in table b, and a.a_id is the value you're truing to insert into that column.
If you just want to skip the insert when a matching row already exists, then use MERGE instead of INSERT.