How to catch a unique constraint error in a PL/SQL block?

Question

Say I have an Oracle PL/SQL block that inserts a record into a table and need to recover from a unique constraint error, like this:

begin
    insert into some_ta         


        

Answer 1

I'm sure you have your reasons, but just in case... you should also consider using a "merge" query instead:

begin
    merge into some_table st
    using (select 'some' name, 'values' value from dual) v
    on (st.name=v.name)
    when matched then update set st.value=v.value
    when not matched then insert (name, value) values (v.name, v.value);
end;

(modified the above to be in the begin/end block; obviously you can run it independantly of the procedure too).