DECLARE	v_day varchar2(2);	v_month varchar2(2);	v_sqlstr varchar2(500);BEGIN	v_day:= to_char(sysdate-1,'fmdd');		v_month :=to_char(sysdate,'fmmm');	dbms_output.put_line(v_day);	v_sqlstr:='insert into shy_month_'||v_month||'(select login_name,trunc(sysdate-1,''dd''),lab_ip,sum(time_duration) from shy_day_'||v_day||' where logout_date>trunc(sysdate-1,''fmdd'') and logout_date< trunc(sysdate,''fmdd'') group by login_name,lab_ip)';	execute immediate v_sqlstr;	commit;	dbms_output.put_line(v_sqlstr);END;