oracle 使用leading, use_nl, rownum调优例证

2013-10-04

oracle 使用leading, use_nl, rownum调优例子select /*+ leading(e) use_nl(sc) */ count(sc.pmnum)into v

oracle 使用leading, use_nl, rownum调优例子
select /*+ leading(e) use_nl(sc) */ count(sc.pmnum) into v_count from equipment e, sal_controledpnsnrange sc where (sc.new_min_item_no <= e.itemnum) and (sc.new_max_item_no >= e.itemnum) and (sc.new_min_serial_no <= e.serialnum) and (sc.new_max_serial_no >= e.serialnum) and e.itemnum = a_item_no and rownum = 1;