Oracle Sequence与Trigger的使用

            --
             Create sequence 
            create
             sequence SEQ_PUSH
minvalue 
            1
            
maxvalue 
            9999999999
            
start 
            with
            1
            
increment 
            by
            1
            
cache 
            20;

            create
            or
            replace
            trigger
             tr_id_insert
  before 
            insert
            on
             t_push  
  
            for
             each row

            declare
            --
             local variables here
            begin
            select seq_user_id.nextval into :new.id from dual;
end tr_id_insert;