+

运算符说明

+ 运算符用于加法运算。

语法结构

1. > SELECT value1+value2;

1. > SELECT column1+column2... FROM table_name;

示例

1. mysql> select 1123.2333+1233.3331;
2. +-----------------------+
3. | 1123.2333 + 1233.3331 |
4. +-----------------------+
5. |             2356.5664 |
6. +-----------------------+
7. 1 row in set (0.01 sec)

1. create table t2(c1 int, c2 int);
2. insert into t2 values (-3, 2);
3. insert into t2 values (1, 2);

5. mysql> select c1+5 from t2;
6. +--------+
7. | c1 + 5 |
8. +--------+
9. |      2 |
10. |      6 |
11. +--------+
12. 2 rows in set (0.00 sec)

14. mysql> select c1+c2 from t2;
15. +---------+
16. | c1 + c2 |
17. +---------+
18. |      -1 |
19. |       3 |
20. +---------+
21. 2 rows in set (0.00 sec)