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create sequence TestIdentity
  start with 1
  increment by 1
  maxvalue 99999
  nocycle
  cache 20;

create or replace trigger TestTrigger
  before insert on test for each row
    begin
      select TestIdentity.nextval into:new.ID from dual;
    end;

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select TestIdentity.currval into:new.ID from dual;
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insert intoÓï¾ä¿´¿´

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insert into sysadmin.test values(TestIdentity.nextval,'abd',to_date('2009-06-23','YYYY-MM-DD'))

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SQL> create table test (id number,name varchar2(16)