mysql - 汇总列中的 bigint 值

Question

我在 mysql (v 5.6.23) 中有一个表，描述如下:

mysql> describe as_dcm_testing;
+--------------+-------------+------+-----+---------+-------+
| Field        | Type        | Null | Key | Default | Extra |
+--------------+-------------+------+-----+---------+-------+
| LCID         | varchar(32) | NO   | PRI | NULL    |       |
| LASTACTIVITY | varchar(32) | YES  |     | NULL    |       |
| USAGE        | bigint(20)  | YES  |     | NULL    |       |
| SERVICELEVEL | varchar(16) | YES  |     | NULL    |       |
+--------------+-------------+------+-----+---------+-------+
4 rows in set (0.01 sec)

我想对 USAGE 列中的所有值求和，所以我尝试使用 sum 函数。问题是我似乎遇到了错误。这个错误是因为使用的是 BIGINT 而不是 INT 吗？如何对具有 bigint 值的列中的值求和？

mysql> select SUM(USAGE) as usage from as_dcm_testing;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'USAGE) as usage from as_dcm_testing' at line 1
mysql>

提前致谢

一个

Answer 1

USAGE是MySQL中的保留字。您必须将其括在反引号中:

select SUM(`USAGE`) as `usage` from as_dcm_testing;