有没有办法在存储过程中告诉您的主机名？

Question

有没有办法在存储过程中确定您正在运行的服务器的主机名？

您可以从客户端运行系统主机名，但不能从 SP 进行系统调用。我没有看到任何全局变量或状态。

Answer 1

我可以在我的 PC 上看到我的主机名

mysql> show variables like 'hostname';
+---------------+--------------+
| Variable_name | Value        |
+---------------+--------------+
| hostname      | LW-REDWARDS2 |
+---------------+--------------+
1 row in set (0.00 sec)

mysql>

这适用于 MySQL 5.x

SELECT variable_value INTO @local_hostname
FROM information_schema.global_variables
WHERE variable_name = 'hostname';

该查询直接在 mysql 客户端中工作：

mysql> SELECT variable_value INTO @local_hostname
    -> FROM information_schema.global_variables
    -> WHERE variable_name = 'hostname';
Query OK, 1 row affected (0.00 sec)

mysql> select @local_hostname;
+-----------------+
| @local_hostname |
+-----------------+
| LW-REDWARDS2    |
+-----------------+
1 row in set (0.00 sec)

mysql>

这是我在我的 PC 上用 MySQL 5.5.12 编写的快速 SP

DELIMITER $$

DROP PROCEDURE IF EXISTS `junk`.`ShowHostName` $$
CREATE PROCEDURE `junk`.`ShowHostName` ()
BEGIN

    SELECT variable_value INTO @local_hostname
    FROM information_schema.global_variables
    WHERE variable_name = 'hostname';
    SELECT @local_hostname;

END $$

DELIMITER ;

然后运行 CALL junk.ShowHostName();

mysql> CALL junk.ShowHostName();
+-----------------+
| @local_hostname |
+-----------------+
| LW-REDWARDS2    |
+-----------------+
1 row in set (0.00 sec)

Query OK, 0 rows affected (0.01 sec)

mysql>

这是一个函数

DELIMITER $$

DROP FUNCTION IF EXISTS `junk`.`GetHostName` $$
CREATE FUNCTION `junk`.`GetHostName` () RETURNS VARCHAR(64)
DETERMINISTIC
BEGIN

    DECLARE local_hostname VARCHAR(64);

    SELECT variable_value INTO local_hostname
    FROM information_schema.global_variables
    WHERE variable_name = 'hostname';

    RETURN local_hostname;

END $$

DELIMITER ;

现在，只需选择它：

mysql> SELECT junk.GetHostName();
+--------------------+
| junk.GetHostName() |
+--------------------+
| LW-REDWARDS2       |
+--------------------+
1 row in set (0.00 sec)

mysql>

试一试 ！！！