1楼说的是对的,补充一点,如果粗橘想走多个索引岩汪团的话可陵让以这样:select/*+INDEX(a IDX_a_1)INDEX(b IDX_b_2)INDEX(c IDX_c_2)*/ *from table1 a,table2 b,table3 cwhere a.id=b.id and b.id = c.fid;