摘要：
--数字型函数select abs (-100) from dual;--绝对值select mod (10,3) from dual;--求模select ceil (12.5) from dual;--取上限整数select floor (12.5) from dual;--取下限整数selec... 阅读全文
摘要：
--内连接 两种写法 等值连接select r.*,b.bummc from t_hq_ryxx r, t_hq_bm b where r.bumbm = b.bumbmselect r.*,b.bummc from t_hq_ryxx r inner join t_hq_bm b on r.bum... 阅读全文