Oracle SQL语句实现数字四舍五入取整
时间：2021-01-10 11:04:54|栏目：Oracle|点击： 次
取整（向下取整）：
复制代码 代码如下:
select floor(5.534) from dual;
select trunc(5.534) from dual;
select trunc(5.534) from dual;
上面两种用法都可以对数字5.534向下取整，结果为5.
如果要向上取整 ，得到结果为6，则应该用ceil
复制代码 代码如下:
select ceil(5.534) from dual;
四舍五入：
复制代码 代码如下:
SELECT round(5.534) FROM dual;
SELECT round(5.534,0) FROM dual;
SELECT round(5.534,1) FROM dual;
SELECT round(5.534,2) FROM dual;
SELECT round(5.534,0) FROM dual;
SELECT round(5.534,1) FROM dual;
SELECT round(5.534,2) FROM dual;
结果分别为 6, 6, 5.5, 5.53
保留N位小数（不四舍五入）：
复制代码 代码如下:
select trunc(5.534,0) from dual;
select trunc(5.534,1) from dual;
select trunc(5.534,2) from dual;
select trunc(5.534,1) from dual;
select trunc(5.534,2) from dual;
结果分别是 5,5.5,5.53，其中保留0位小数就相当于直接取整了。
数字格式化：
复制代码 代码如下:
select to_char(12345.123,'99999999.9999') from dual;
结果为12345.123
复制代码 代码如下:
select to_char(12345.123,'99999999.9900') from dual;
小数后第三第四为不足补0，结果为12345.1230
复制代码 代码如下:
select to_char(0.123,'99999999.9900') from dual;
select to_char(0.123,'99999990.9900') from dual;
select to_char(0.123,'99999990.9900') from dual;
结果分别为 .123, 0.123
