Oracle Sequence for Auto-Increment |
create sequence product_seq start with 1 increment 1 / create or replace trigger product_insert before insert for each row begin select productseq.nextval into :new.product_id from dual; end; /
How to create an autoincrement field in a table with a sequence ... SQLWKS> create table bob(a number , b varchar2(21)); Statement processed. First create a sequence SQLWKS> create sequence x ; Statement processed. Then create the trigger. create trigger y before insert on bob for each row when (new.a is null) begin select x.nextval into :new.a from dual; end; /
First create a sequence: create sequence emp_no_seq; By default it increments by 1 starting at 0. Use its values when inserting data into the table: insert into t_emp values (emp_no_seq.nexval, 'Joe Black');