1.创建SEQUENCE（自增长列 与表无关）
CREATE SEQUENCE "CEIADM_TASKS_SEQ" MINVALUE 1 MAXVALUE 99999999 INCREMENT BY 1 START WITH 1 NOCACHE
2.创建触发器，关联表
CREATE OR REPLACE TRIGGER "INSERT_CEIADM_TASKS"
BEFORE
insert on "CEIADM_TASKS"
for each row
begin
select "CEIADM_TASKS_SEQ".nextval into :NEW.TASK_ID from dual;
end;
BEFORE
insert on "CEIADM_TASKS"
for each row
begin
select "CEIADM_TASKS_SEQ".nextval into :NEW.TASK_ID from dual;
end;