Oracle数据库监控软件(简称Oracle监控或Oracle监控软件)是企事业单位中最重要的监控需要，通过对Oracle数据库的监控，可以全面了解Oracle的运行状态、数据库响应情况、数据库表空用度情况。

SUM服务器监控软件对Oracle数据库的监控十分全面，主要有：缓冲区命中率监控、表空间使用率监控、表空间监控、会话数监控、连接数监控等核心性能，这些性能均为DBA必须了解和随时掌握的性能，SUM的监控为DBA提供了有力的帮助。在Oracle数据库的性能监控中其中表空间随时监控是DBA首要职责，因为一旦表空用尽，将无法再进行数据库的操作，这将给应用软件造成很大的损失。通过SUM监控与短信报警功能，DBA可以设定表空间使用率阀值进行报警，比如可以设定表空间使用率达到95%后就立即短信通知指定的DBA进行表空间扩容，从而可以有效地避免因为表空间不足引起的应用程序错误和数据库错误。

mysql中的事件调度器可以定时对数据库增加,删除和执行操作,相当于数据库中的临时触发器,与Linux系统中的执行计划任务一样,这样就可以大大降低工作量.

1.开启事件调度器

[root@node1 ~]# vim /usr/my.cnf         --在配置文件中加入以下语句启用调度器

event_scheduler=1

[root@node1 ~]# /etc/init.d/mysql restart

ERROR! MySQL server PID file could not be found!

Starting MySQL... SUCCESS!

[root@node1 ~]#

2.查看事件调度是否开启

[root@node1 ~]# mysql -u root -p

Enter password:

Welcome to the MySQL monitor.  Commands end with ; or \g.

Your MySQL connection id is 2

Server version: 5.6.21 MySQL Community Server (GPL)

Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its

affiliates. Other names may be trademarks of their respective

owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show variables like "event_%";           --查看调度器是否启用

+-----------------+-------+

| Variable_name   | Value |

+-----------------+-------+

| event_scheduler | ON    |

+-----------------+-------+

1 row in set (0.00 sec)

mysql> ? create event;              --查看创建事件的语法

Name: 'CREATE EVENT'

Description:

Syntax:

CREATE

[DEFINER = { user | CURRENT_USER }]

EVENT

[IF NOT EXISTS]

event_name

ON SCHEDULE schedule

[ON COMPLETION [NOT] PRESERVE]

[ENABLE | DISABLE | DISABLE ON SLAVE]

[COMMENT 'comment']

DO event_body;

schedule:

AT timestamp [+ INTERVAL interval] ...

| EVERY interval

[STARTS timestamp [+ INTERVAL interval] ...]

[ENDS timestamp [+ INTERVAL interval] ...]

interval:

quantity {YEAR | QUARTER | MONTH | DAY | HOUR | MINUTE |

WEEK | SECOND | YEAR_MONTH | DAY_HOUR | DAY_MINUTE |

DAY_SECOND | HOUR_MINUTE | HOUR_SECOND | MINUTE_SECOND}

mysql> create database test123;

Query OK, 1 row affected (0.00 sec)

mysql> \u test123

Database changed

mysql>

3.创建事件调度5秒钟后创建t表

mysql> create event if not exists event_t on schedule at current_timestamp + interval 5 second  do create table t (a int,b nchar(10),c timestamp);

Query OK, 0 rows affected (0.00 sec)

mysql> show events;        --查看事件是否创建成功

+---------+----------+----------------+-----------+-----------+------------+----------------+----------------+---------------------+------+---------+------------+----------------------+----------------------+--------------------+

| Db      | Name     | Definer        | Time zone | Type      | Execute at | Interval value | Interval field | Starts              | Ends | Status  | Originator | character_set_client | collation_connection | Database Collation |

+---------+----------+----------------+-----------+-----------+------------+----------------+----------------+---------------------+------+---------+------------+----------------------+----------------------+--------------------+

| test123 | event_t1 | root@localhost | SYSTEM    | RECURRING | NULL       | 5              | SECOND         | 2014-11-12 15:29:13 | NULL | ENABLED |          0 | utf8                 | utf8_general_ci      | latin1_swedish_ci  |

+---------+----------+----------------+-----------+-----------+------------+----------------+----------------+---------------------+------+---------+------------+----------------------+----------------------+--------------------+

1 row in set (0.00 sec)

mysql> show tables;

Empty set (0.00 sec)

mysql> show tables;               --创建表成功

+-------------------+

| Tables_in_test123 |

+-------------------+

| t                 |

+-------------------+

1 row in set (0.00 sec)

mysql> desc t;

+-------+-----------+------+-----+-------------------+-----------------------------+

| Field | Type      | Null | Key | Default           | Extra                       |

+-------+-----------+------+-----+-------------------+-----------------------------+

| a     | int(11)   | YES  |     | NULL              |                             |

| b     | char(10)  | YES  |     | NULL              |                             |

| c     | timestamp | NO   |     | CURRENT_TIMESTAMP | on update CURRENT_TIMESTAMP |

+-------+-----------+------+-----+-------------------+-----------------------------+

3 rows in set (0.01 sec)

mysql>

4.创建事件调度每5秒在表中插入数据

mysql> create event if not exists event_t1 on schedule every  5 second  do insert into t values(1,1,sysdate());

Query OK, 0 rows affected (0.01 sec)

mysql> select * from t;           --查看事件执行数据

+------+------+---------------------+

| a    | b    | c                   |

+------+------+---------------------+

|    1 | 1    | 2014-11-12 15:33:31 |

|    1 | 1    | 2014-11-12 15:33:36 |

|    1 | 1    | 2014-11-12 15:33:41 |

|    1 | 1    | 2014-11-12 15:33:46 |

|    1 | 1    | 2014-11-12 15:33:51 |

|    1 | 1    | 2014-11-12 15:33:56 |

|    1 | 1    | 2014-11-12 15:34:01 |

+------+------+---------------------+

7 rows in set (0.00 sec)

mysql>

5.创建事件调度10秒钟后删除t表中所有数据

mysql> create event if not exists event_t2 on schedule every  10  second  do truncate table t;

Query OK, 0 rows affected (0.00 sec)

mysql> select * from t;

+------+------+---------------------+

| a    | b    | c                   |

+------+------+---------------------+

|    1 | 1    | 2014-11-12 15:36:36 |

|    1 | 1    | 2014-11-12 15:36:41 |

+------+------+---------------------+

2 rows in set (0.00 sec)

mysql> select * from t;

Empty set (0.00 sec)

mysql>

6.在指定时间删除t表数据

mysql> create event if not exists event_t2 on schedule at timestamp '2014-11-12 15:39:00' do truncate table t;;

Query OK, 0 rows affected, 1 warning (0.02 sec)

mysql> select * from t;

Empty set (0.00 sec)

mysql>

7.创建事件调度每天删除t表数据

mysql> create event if not exists event_t2 on schedule every 1 day  do truncate table t;

Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> select * from t;

Empty set (0.00 sec)

mysql>

8.创建事件调度5天后开启删除t表中数据,一个月后停止

mysql> create event if not exists event_t2 on schedule every 1 day  starts current_timestamp + interval 5 day ends current_timestamp + interval 1 month do truncate table t;

Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql>

9.禁用事件调度器

mysql> alter  event event_t2 disable;

Query OK, 0 rows affected (0.00 sec)

mysql>

10.启用事件调度器

mysql> alter  event event_t2 enable;

Query OK, 0 rows affected (0.00 sec)

mysql>

11.修改事件调度器10天后启用

mysql> alter  event event_t2 on schedule every 10 day;

Query OK, 0 rows affected (0.00 sec)

mysql>

12.重命名事件调度器

mysql> alter event event_t2 rename to event_t1;

Query OK, 0 rows affected (0.00 sec)

mysql>

13.查看事件调度器的信息

mysql> show events like "event_t1" \G;

*************************** 1. row ***************************

Db: test123

Name: event_t1

Definer: root@localhost

Time zone: SYSTEM

Type: RECURRING

Execute at: NULL

Interval value: 10

Interval field: DAY

Starts: 2014-11-12 15:47:31

Ends: NULL

Status: ENABLED

Originator: 0

character_set_client: utf8

collation_connection: utf8_general_ci

Database Collation: latin1_swedish_ci

1 row in set (0.00 sec)

ERROR:

No query specified

mysql>

14.查看事件调度器的内容

mysql> show create event event_t1 \G;

*************************** 1. row ***************************

Event: event_t1

sql_mode: STRICT_TRANS_TABLES,NO_ENGINE_SUBSTITUTION

time_zone: SYSTEM

Create Event: CREATE DEFINER=`root`@`localhost` EVENT `event_t1` ON SCHEDULE EVERY 10 DAY STARTS '2014-11-12 15:47:31' ON COMPLETION NOT PRESERVE ENABLE DO truncate table t

character_set_client: utf8

collation_connection: utf8_general_ci

Database Collation: latin1_swedish_ci

1 row in set (0.00 sec)

ERROR:

No query specified

mysql>