How to create an auto-increment field in a table in Oracle

How to create an auto-increment field in a table in Oracle
This method uses SEQUENCE (SEQUENCE). For example, the structure of table temp_test is: create table TEMP_TEST.
(
Id number,
Nm varchar (10 ),
Primary key (id) // id is the primary key. The following method sets it as an auto-increment Field
) 1. CREATE an auto-incrementing SEQUENCE TEMP_TEST_IDADD. The name is arbitrary. START from 1 and Add 1 create sequence TEMP_TEST_IDADD increment by 1 start with 1 each time; 2. CREATE a TRIGGER in the table temp_test as follows: create or replace trigger T_TEMP_TEST_IDADD
Before insert on TEMP_TEST
FOR EACH ROW
BEGIN
SELECT TEMP_TEST_IDADD.NEXTVAL INTO: NEW. id from dual;
END T_TEMP_TEST_IDADD; Test Result: add data to the temp_test table and execute the following statement to insert into TEMP_TEST (nm) twice)
Values ('ss'); the result is as follows: