第六周作业

1.简述DDL,DML,DCL,DQL，并且说明mysql各个关键字查询时候的先后顺序

DDL 定义语言：CREATE创建 DROP删除 ALTER修改
DML操作语言: INSERT增加 DELETE删除 UPDATE改
DQL查询语言： SELECT查
DCL控制语言: GRANT授权 REVOKE取消授权

在SQL语句中每个关键字都会按照顺序往下执行，而每一步操作，会生成一个虚拟表，最后的虚拟表就是最终结果。

FROM ： 对FROM左边的表和右边的表计算笛卡尔积，产生虚表VT1；
ON ： 对虚拟表VT1进行ON筛选，只有那些符合条件的行才会被记录在虚拟表VT2中；
JOIN ：如果是OUT JOIN，那么将保留表中（如左表或者右表）未匹配的行作为外部行添加到虚拟表VT2中，从而产生虚拟表VT3；
WHERE ：对虚拟表VT3进行WHERE条件过滤，只有符合的记录才会被放入到虚拟表VT4；
GROUP BY：根据GROUP BY子句中的列，对虚拟表VT4进行分组操作，产生虚拟表VT5；
CUBE|ROLLUP：对虚拟表VT5进行CUBE或者ROLLUP操作，产生虚拟表VT6；
HAVING ：对虚拟表VT6进行 HAVING 条件过滤，只有符合的记录才会被插入到虚拟表VT7中；
SELECT ：执行SELECT操作，选择指定的列，插入到虚拟表VT8中；
DISTINCT ：对虚拟表VT8中的记录进行去重，产生虚拟表VT9；
ORDER BY ：将虚拟表VT9中的记录按照进行排序操作，产生虚拟表VT10；
LIMIT ：取出指定行的记录，产生虚拟表VT11，并将结果返回。

2. 自行设计10个sql查询语句，需要用到关键字[GROUP BY/HAVING/ORDER BY/LIMIT]，至少同时用到两个

  • order by 和 limit 排序后提取前三个
(root@localhost) [hellodb]> select * from students order by age limit 3;
+-------+-------------+-----+--------+---------+-----------+
| StuID | Name        | Age | Gender | ClassID | TeacherID |
+-------+-------------+-----+--------+---------+-----------+
|    14 | Lu Wushuang |  17 | F      |       3 |      NULL |
|     8 | Lin Daiyu   |  17 | F      |       7 |      NULL |
|    19 | Xue Baochai |  18 | F      |       6 |      NULL |
+-------+-------------+-----+--------+---------+-----------+
3 rows in set (0.01 sec)
  • group by 和 having 分组求平均值
(root@localhost) [hellodb]> select gender,avg(age)  from students group by gender having gender='F';
+--------+----------+
| gender | avg(age) |
+--------+----------+
| F      |  19.0000 |
+--------+----------+
1 row in set (0.00 sec)
  • group by 和 order by 分组排序
(root@localhost) [hellodb]> select classid,count(*) 数量  from students group by classid  order by 数量;
+---------+--------+
| classid | 数量   |
+---------+--------+
|       5 |      1 |
|    NULL |      2 |
|       2 |      3 |
|       7 |      3 |
|       1 |      4 |
|       4 |      4 |
|       3 |      4 |
|       6 |      4 |
+---------+--------+
8 rows in set (0.00 sec)
  • group by和order by 分组显示并排序
(root@localhost) [hellodb]> select gender,classid,avg(age) from students where classid is not null group by gender,classid order by classid,classid;
+--------+---------+----------+
| gender | classid | avg(age) |
+--------+---------+----------+
| M      |       1 |  21.5000 |
| F      |       1 |  19.5000 |
| M      |       2 |  36.0000 |
| M      |       3 |  26.0000 |
| F      |       3 |  18.3333 |
| M      |       4 |  24.7500 |
| M      |       5 |  46.0000 |
| F      |       6 |  20.0000 |
| M      |       6 |  23.0000 |
| F      |       7 |  18.0000 |
| M      |       7 |  23.0000 |
+--------+---------+----------+
11 rows in set (0.00 sec)
  • like 和 order by
(root@localhost) [hellodb]> select * from students where name like'x%' order by classid;
+-------+-------------+-----+--------+---------+-----------+
| StuID | Name        | Age | Gender | ClassID | TeacherID |
+-------+-------------+-----+--------+---------+-----------+
|    24 | Xu Xian     |  27 | M      |    NULL |      NULL |
|    16 | Xu Zhu      |  21 | M      |       1 |      NULL |
|    22 | Xiao Qiao   |  20 | F      |       1 |      NULL |
|     3 | Xie Yanke   |  53 | M      |       2 |        16 |
|     7 | Xi Ren      |  19 | F      |       3 |      NULL |
|    19 | Xue Baochai |  18 | F      |       6 |      NULL |
+-------+-------------+-----+--------+---------+-----------+
6 rows in set (0.00 sec)
  • not null 和order by
(root@localhost) [hellodb]> select * from students where classid is not null order by StuID;
+-------+---------------+-----+--------+---------+-----------+
| StuID | Name          | Age | Gender | ClassID | TeacherID |
+-------+---------------+-----+--------+---------+-----------+
|     1 | Shi Zhongyu   |  22 | M      |       2 |         3 |
|     2 | Shi Potian    |  22 | M      |       1 |         7 |
|     3 | Xie Yanke     |  53 | M      |       2 |        16 |
|     4 | Ding Dian     |  32 | M      |       4 |         4 |
|     5 | Yu Yutong     |  26 | M      |       3 |         1 |
|     6 | Shi Qing      |  46 | M      |       5 |      NULL |
|     7 | Xi Ren        |  19 | F      |       3 |      NULL |
|     8 | Lin Daiyu     |  17 | F      |       7 |      NULL |
|     9 | Ren Yingying  |  20 | F      |       6 |      NULL |
|    10 | Yue Lingshan  |  19 | F      |       3 |      NULL |
|    11 | Yuan Chengzhi |  23 | M      |       6 |      NULL |
|    12 | Wen Qingqing  |  19 | F      |       1 |      NULL |
|    13 | Tian Boguang  |  33 | M      |       2 |      NULL |
|    14 | Lu Wushuang   |  17 | F      |       3 |      NULL |
|    15 | Duan Yu       |  19 | M      |       4 |      NULL |
|    16 | Xu Zhu        |  21 | M      |       1 |      NULL |
|    17 | Lin Chong     |  25 | M      |       4 |      NULL |
|    18 | Hua Rong      |  23 | M      |       7 |      NULL |
|    19 | Xue Baochai   |  18 | F      |       6 |      NULL |
|    20 | Diao Chan     |  19 | F      |       7 |      NULL |
|    21 | Huang Yueying |  22 | F      |       6 |      NULL |
|    22 | Xiao Qiao     |  20 | F      |       1 |      NULL |
|    23 | Ma Chao       |  23 | M      |       4 |      NULL |
+-------+---------------+-----+--------+---------+-----------+
23 rows in set (0.00 sec)
  • order 和 limit
(root@localhost) [hellodb]> select * from students where classid is not null order by StuID limit 3;
+-------+-------------+-----+--------+---------+-----------+
| StuID | Name        | Age | Gender | ClassID | TeacherID |
+-------+-------------+-----+--------+---------+-----------+
|     1 | Shi Zhongyu |  22 | M      |       2 |         3 |
|     2 | Shi Potian  |  22 | M      |       1 |         7 |
|     3 | Xie Yanke   |  53 | M      |       2 |        16 |
+-------+-------------+-----+--------+---------+-----------+
3 rows in set (0.00 sec)

3. xtrabackup备份和还原数据库练习

master机器

[root@10_0_0_30 ~]$yum -y install percona-xtrabackup-80-8.0.33-28.1.el8.x86_64.rpm
[root@10_0_0_30 ~]$xtrabackup -uroot -p123456 --backup --target-dir=/backup/base
[root@10_0_0_30 /backup/base]$scp -r /backup/ 10.0.0.134:/

还原机器

[root@server ~]# ls /backup/                #查看复制过来的backup
base
[root@server ~]yum -y install mysql-server     #安装MYSQLD
[root@server ~] yum -y install lrzsz                 #安装传输工具
[root@server ~] yum -y install percona-xtrabackup-80-8.0.33-28.1.el8.x86_64.rpm   #安装xtrabackup工具
[root@server ~] xtrabackup --prepare --target-dir=/backup/base    #整理还原事务
[root@server mysql] xtrabackup --copy-back -target-dir=/backup/base     #还原
[root@server mysql] chown -R mysql:mysql /var/lib/mysql    #授权
[root@server mysql] service mysqld start        #重启
Redirecting to /bin/systemctl start mysqld.service
root@server mysql]# mysql -uroot -p123456
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| hellodb            |
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
5 rows in set (0.00 sec)

4. 实现mysql主从复制，主主复制和半同步复制

master:151 slaver:134

1.主从复制

确认主上数据库

mysql root@(none):(none)> show databases
+--------------------+
| Database           |
+--------------------+
| hellodb            |
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+

修改master主节点的配置

[root@151 ~]# cat /etc/my.cnf
#
# This group is read both both by the client and the server
# use it for options that affect everything
#
[client-server]

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d
[client]
user=root
password=123456
[mysqld]
server_id=151
log-bin=/data/mysql/log/mysql-bin
log_error=/data/mysql/log/error.log
innodb-flush-log-at-trx-commit=2
general_log = ON
slow_query_log = ON
long_query_time = 3

重启mysqld

[root@151 ~]# systemctl restart mysqld

创建复制用户并授权

mysql root@(none):(none)> create user 'slaver134'@'10.0.0.%' identified by '123456';

grant replication slave on *.* to 'slaver134'@'10.0.0.%';

Query OK, 0 rows affected (0.01 sec)

配置从节点

[root@134 ~]# cat /etc/my.cnf
#
# This group is read both both by the client and the server
# use it for options that affect everything
#
[client-server]

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d

[client]
user=root
password=123456
[mysqld]
server_id=134
log-bin = /data/mysql/log/mysql.bin
read_only=ON

创建binlog文件夹并且授权后重启mysqld

[root@134 ~]# mkdir -p /data/mysql/log/
[root@134 ~]# chown mysql:mysql /data/mysql/log/
[root@134 ~]# ll /data/mysql/
total 0
drwxr-xr-x 2 mysql mysql 6 Jan  5 13:50 log
[root@134 ~]# systemctl restart mysqld

查看主151上的binlog文件位置

mysql root@(none):(none)> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000006 | 157      |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+

1 row in set
Time: 0.009s

修改CHANGE MASTER TO并启动sql线程:

mysql>  CHANGE MASTER TO
    ->   MASTER_HOST='10.0.0.151',
    ->   MASTER_USER='slaver134',
    ->   MASTER_PASSWORD='123456',
    ->   MASTER_PORT=3306,
    ->   MASTER_LOG_FILE='mysql-bin.000006',
    ->   MASTER_LOG_POS=157;
Query OK, 0 rows affected, 9 warnings (0.03 sec)

mysql> start slave;

mysql> show slave status\G;
*************************** 1. row ***************************
               Slave_IO_State: Waiting for source to send event
                  Master_Host: 10.0.0.151
                  Master_User: slaver134
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000006
          Read_Master_Log_Pos: 157
               Relay_Log_File: 134-relay-bin.000002
                Relay_Log_Pos: 326
        Relay_Master_Log_File: mysql-bin.000006
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB:
          Replicate_Ignore_DB:
           Replicate_Do_Table:
       Replicate_Ignore_Table:
      Replicate_Wild_Do_Table:
  Replicate_Wild_Ignore_Table:
                   Last_Errno: 0
                   Last_Error:
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 157
              Relay_Log_Space: 534
              Until_Condition: None
               Until_Log_File:
                Until_Log_Pos: 0
           Master_SSL_Allowed: No
           Master_SSL_CA_File:
           Master_SSL_CA_Path:
              Master_SSL_Cert:
            Master_SSL_Cipher:
               Master_SSL_Key:
        Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno: 0
                Last_IO_Error:
               Last_SQL_Errno: 0
               Last_SQL_Error:
  Replicate_Ignore_Server_Ids:
             Master_Server_Id: 151
                  Master_UUID: 42900a2b-a146-11ee-ba4c-000c29e3468a
             Master_Info_File: mysql.slave_master_info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: Replica has read all relay log; waiting for more updates
           Master_Retry_Count: 86400
                  Master_Bind:
      Last_IO_Error_Timestamp:
     Last_SQL_Error_Timestamp:
               Master_SSL_Crl:
           Master_SSL_Crlpath:
           Retrieved_Gtid_Set:
            Executed_Gtid_Set:
                Auto_Position: 0
         Replicate_Rewrite_DB:
                 Channel_Name:
           Master_TLS_Version:
       Master_public_key_path:
        Get_master_public_key: 0
            Network_Namespace:
1 row in set, 1 warning (0.00 sec)

确认主 从服务器线程情况:

master:151

mysql root@(none):(none)> show processlist;
+----+-----------------+------------------+--------+-------------+------+-----------------------------------------------------------------+------------------+
| Id | User            | Host             | db     | Command     | Time | State                                                           | Info             |
+----+-----------------+------------------+--------+-------------+------+-----------------------------------------------------------------+------------------+
| 5  | event_scheduler | localhost        | <null> | Daemon      | 1325 | Waiting on empty queue                                          | <null>           |
| 8  | root            | localhost        | <null> | Query       | 0    | init                                                            | show processlist |
| 12 | slaver134       | 10.0.0.134:36136 | <null> | Binlog Dump | 178  | Source has sent all binlog to replica; waiting for more updates | <null>           |
+----+-----------------+------------------+--------+-------------+------+-----------------------------------------------------------------+------------------+

3 rows in set
Time: 0.005s

slaver:134

mysql> show processlist;
+----+-----------------+-----------------+------+---------+------+----------------------------------------------------------+------------------+
| Id | User            | Host            | db   | Command | Time | State                                                    | Info             |
+----+-----------------+-----------------+------+---------+------+----------------------------------------------------------+------------------+
|  5 | event_scheduler | localhost       | NULL | Daemon  |  822 | Waiting on empty queue                                   | NULL             |
|  8 | root            | localhost       | NULL | Query   |    0 | init                                                     | show processlist |
| 15 | system user     | connecting host | NULL | Connect |  214 | Waiting for source to send event                         | NULL             |
| 16 | system user     |                 | NULL | Query   |  214 | Replica has read all relay log; waiting for more updates | NULL             |
| 17 | system user     |                 | NULL | Connect |  214 | Waiting for an event from Coordinator                    | NULL             |
| 18 | system user     |                 | NULL | Connect |  214 | Waiting for an event from Coordinator                    | NULL             |
| 19 | system user     |                 | NULL | Connect |  214 | Waiting for an event from Coordinator                    | NULL             |
| 20 | system user     |                 | NULL | Connect |  214 | Waiting for an event from Coordinator                    | NULL             |
+----+-----------------+-----------------+------+---------+------+----------------------------------------------------------+------------------+
8 rows in set (0.00 sec)

测试主从复制

151上创建test1数据库

mysql root@(none):(none)> create database test1;
Query OK, 1 row affected
Time: 0.003s
mysql root@(none):(none)> show databases;
+--------------------+
| Database           |
+--------------------+
| hellodb            |
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| test1              |
+--------------------+
6 rows in set
Time: 0.005s

134上查看:

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| hellodb            |
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| test1              |
+--------------------+
6 rows in set (0.00 sec)

3.半同步复制

master:151 slave1:134 slave2:145

master安装半同步模块

mysql root@(none):(none)> install plugin rpl_semi_sync_master soname 'semisync_master.so';
Query OK, 0 rows affected
Time: 0.001s
mysql root@(none):(none)> show plugins;
+---------------------------------+----------+--------------------+--------------------+---------+
| Name                            | Status   | Type               | Library            | License |
+---------------------------------+----------+--------------------+--------------------+---------+
| binlog                          | ACTIVE   | STORAGE ENGINE     | <null>             | GPL     |
| mysql_native_password           | ACTIVE   | AUTHENTICATION     | <null>             | GPL     |
| sha256_password                 | ACTIVE   | AUTHENTICATION     | <null>             | GPL     |
| caching_sha2_password           | ACTIVE   | AUTHENTICATION     | <null>             | GPL     |
| sha2_cache_cleaner              | ACTIVE   | AUDIT              | <null>             | GPL     |
| daemon_keyring_proxy_plugin     | ACTIVE   | DAEMON             | <null>             | GPL     |
| CSV                             | ACTIVE   | STORAGE ENGINE     | <null>             | GPL     |
| MEMORY                          | ACTIVE   | STORAGE ENGINE     | <null>             | GPL     |
| InnoDB                          | ACTIVE   | STORAGE ENGINE     | <null>             | GPL     |
| INNODB_TRX                      | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_CMP                      | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_CMP_RESET                | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_CMPMEM                   | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_CMPMEM_RESET             | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_CMP_PER_INDEX            | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_CMP_PER_INDEX_RESET      | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_BUFFER_PAGE              | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_BUFFER_PAGE_LRU          | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_BUFFER_POOL_STATS        | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_TEMP_TABLE_INFO          | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_METRICS                  | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_FT_DEFAULT_STOPWORD      | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_FT_DELETED               | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_FT_BEING_DELETED         | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_FT_CONFIG                | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_FT_INDEX_CACHE           | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_FT_INDEX_TABLE           | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_TABLES                   | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_TABLESTATS               | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_INDEXES                  | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_TABLESPACES              | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_COLUMNS                  | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_VIRTUAL                  | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_CACHED_INDEXES           | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| INNODB_SESSION_TEMP_TABLESPACES | ACTIVE   | INFORMATION SCHEMA | <null>             | GPL     |
| MyISAM                          | ACTIVE   | STORAGE ENGINE     | <null>             | GPL     |
| MRG_MYISAM                      | ACTIVE   | STORAGE ENGINE     | <null>             | GPL     |
| PERFORMANCE_SCHEMA              | ACTIVE   | STORAGE ENGINE     | <null>             | GPL     |
| TempTable                       | ACTIVE   | STORAGE ENGINE     | <null>             | GPL     |
| ARCHIVE                         | ACTIVE   | STORAGE ENGINE     | <null>             | GPL     |
| BLACKHOLE                       | ACTIVE   | STORAGE ENGINE     | <null>             | GPL     |
| FEDERATED                       | DISABLED | STORAGE ENGINE     | <null>             | GPL     |
| ngram                           | ACTIVE   | FTPARSER           | <null>             | GPL     |
| mysqlx_cache_cleaner            | ACTIVE   | AUDIT              | <null>             | GPL     |
| mysqlx                          | ACTIVE   | DAEMON             | <null>             | GPL     |
| rpl_semi_sync_master            | ACTIVE   | REPLICATION        | semisync_master.so | GPL     |
+---------------------------------+----------+--------------------+--------------------+---------+

修改master配置文件

[root@151 ~]# cat /etc/my.cnf
#
# This group is read both both by the client and the server
# use it for options that affect everything
#
[client-server]

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d
[client]
user=root
password=123456
[mysqld]
server_id=151
log-bin=/data/mysql/log/mysql-bin
log_error=/data/mysql/log/error.log
innodb-flush-log-at-trx-commit=2
general_log = ON
slow_query_log = ON
long_query_time = 3
rpl_semi_sync_master_enabled=on
rpl_semi_sync_master_timeout=3000

[root@151 ~]# systemctl restart mysqld

查看半同步服务

mysql root@(none):(none)> select @@rpl_semi_sync_master_enabled;
+--------------------------------+
| @@rpl_semi_sync_master_enabled |
+--------------------------------+
| 1                              |
+--------------------------------+
1 row in set
Time: 0.008s

slave1服务器配置

slave1 安装半同步模块

mysql> install plugin rpl_semi_sync_slave soname 'semisync_slave.so';
Query OK, 0 rows affected, 1 warning (0.02 sec)

mysql> show plugins;
+---------------------------------+----------+--------------------+-------------------+---------+
| Name                            | Status   | Type               | Library           | License |
+---------------------------------+----------+--------------------+-------------------+---------+
| binlog                          | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| mysql_native_password           | ACTIVE   | AUTHENTICATION     | NULL              | GPL     |
| sha256_password                 | ACTIVE   | AUTHENTICATION     | NULL              | GPL     |
| caching_sha2_password           | ACTIVE   | AUTHENTICATION     | NULL              | GPL     |
| sha2_cache_cleaner              | ACTIVE   | AUDIT              | NULL              | GPL     |
| daemon_keyring_proxy_plugin     | ACTIVE   | DAEMON             | NULL              | GPL     |
| CSV                             | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| MEMORY                          | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| InnoDB                          | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| INNODB_TRX                      | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMP                      | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMP_RESET                | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMPMEM                   | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMPMEM_RESET             | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMP_PER_INDEX            | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMP_PER_INDEX_RESET      | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_BUFFER_PAGE              | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_BUFFER_PAGE_LRU          | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_BUFFER_POOL_STATS        | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_TEMP_TABLE_INFO          | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_METRICS                  | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_DEFAULT_STOPWORD      | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_DELETED               | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_BEING_DELETED         | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_CONFIG                | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_INDEX_CACHE           | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_INDEX_TABLE           | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_TABLES                   | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_TABLESTATS               | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_INDEXES                  | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_TABLESPACES              | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_COLUMNS                  | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_VIRTUAL                  | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CACHED_INDEXES           | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_SESSION_TEMP_TABLESPACES | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| MyISAM                          | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| MRG_MYISAM                      | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| PERFORMANCE_SCHEMA              | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| TempTable                       | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| ARCHIVE                         | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| BLACKHOLE                       | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| FEDERATED                       | DISABLED | STORAGE ENGINE     | NULL              | GPL     |
| ngram                           | ACTIVE   | FTPARSER           | NULL              | GPL     |
| mysqlx_cache_cleaner            | ACTIVE   | AUDIT              | NULL              | GPL     |
| mysqlx                          | ACTIVE   | DAEMON             | NULL              | GPL     |
| rpl_semi_sync_slave             | ACTIVE   | REPLICATION        | semisync_slave.so | GPL     |
+---------------------------------+----------+--------------------+-------------------+---------+
46 rows in set (0.00 sec)

修改slave1配置文件

[root@134 ~]# cat /etc/my.cnf
#
# This group is read both both by the client and the server
# use it for options that affect everything
#
[client-server]

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d

[client]
user=root
password=123456
[mysqld]
server_id=134
log-bin = /data/mysql/log/mysql.bin
read_only=ON
rpl_semi_sync_slave_enabled=on


[root@134 ~]# systemctl restart mysqld

查看半同步服务

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

slave2服务器配置

slave2 安装半同步模块

mysql>  install plugin rpl_semi_sync_slave soname 'semisync_slave.so';
Query OK, 0 rows affected, 1 warning (0.01 sec)

mysql>  show plugins;
+---------------------------------+----------+--------------------+-------------------+---------+
| Name                            | Status   | Type               | Library           | License |
+---------------------------------+----------+--------------------+-------------------+---------+
| binlog                          | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| mysql_native_password           | ACTIVE   | AUTHENTICATION     | NULL              | GPL     |
| sha256_password                 | ACTIVE   | AUTHENTICATION     | NULL              | GPL     |
| caching_sha2_password           | ACTIVE   | AUTHENTICATION     | NULL              | GPL     |
| sha2_cache_cleaner              | ACTIVE   | AUDIT              | NULL              | GPL     |
| daemon_keyring_proxy_plugin     | ACTIVE   | DAEMON             | NULL              | GPL     |
| CSV                             | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| MEMORY                          | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| InnoDB                          | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| INNODB_TRX                      | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMP                      | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMP_RESET                | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMPMEM                   | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMPMEM_RESET             | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMP_PER_INDEX            | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CMP_PER_INDEX_RESET      | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_BUFFER_PAGE              | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_BUFFER_PAGE_LRU          | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_BUFFER_POOL_STATS        | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_TEMP_TABLE_INFO          | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_METRICS                  | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_DEFAULT_STOPWORD      | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_DELETED               | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_BEING_DELETED         | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_CONFIG                | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_INDEX_CACHE           | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_FT_INDEX_TABLE           | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_TABLES                   | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_TABLESTATS               | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_INDEXES                  | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_TABLESPACES              | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_COLUMNS                  | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_VIRTUAL                  | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_CACHED_INDEXES           | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| INNODB_SESSION_TEMP_TABLESPACES | ACTIVE   | INFORMATION SCHEMA | NULL              | GPL     |
| MyISAM                          | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| MRG_MYISAM                      | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| PERFORMANCE_SCHEMA              | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| TempTable                       | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| ARCHIVE                         | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| BLACKHOLE                       | ACTIVE   | STORAGE ENGINE     | NULL              | GPL     |
| FEDERATED                       | DISABLED | STORAGE ENGINE     | NULL              | GPL     |
| ngram                           | ACTIVE   | FTPARSER           | NULL              | GPL     |
| mysqlx_cache_cleaner            | ACTIVE   | AUDIT              | NULL              | GPL     |
| mysqlx                          | ACTIVE   | DAEMON             | NULL              | GPL     |
| rpl_semi_sync_slave             | ACTIVE   | REPLICATION        | semisync_slave.so | GPL     |
+---------------------------------+----------+--------------------+-------------------+---------+
46 rows in set (0.01 sec)

修改slave2配置文件

[root@145 /]# cat /etc/my.cnf
#
# This group is read both both by the client and the server
# use it for options that affect everything
#

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d
[client]
user=root
password=123456
[mysqld]
server-id=145
log_bin
read-only
rpl_semi_sync_slave_enabled=on

[root@145 /]# systemctl restart mysqld

查看半同步服务

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

5. 用mycat实现mysql的读写分离(在主从同步的基础上实现)

主:131 从:130 mycat:132

1.配置主从服务器131 和130

[root@131 ~]# cat /etc/my.cnf
#
# This group is read both both by the client and the server
# use it for options that affect everything
#
[client-server]

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d
[client]
user=root
password=123456
[mysqld]
server-id=131
log-bin= /data/mysql/log/mysql-bin

[root@130 /]# cat /etc/my.cnf
#
# This group is read both both by the client and the server
# use it for options that affect everything
#
[client-server]

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d
[client]
user=root
password=123456
[mysqld]
server_id=130
log-bin = /data/mysql/log/mysql.bin
#read_only=ON

mycat 132配置

1.安装jiava

yum -y install java

[root@129 ~]# java -version
openjdk version "1.8.0_392"
OpenJDK Runtime Environment (build 1.8.0_392-b08)
OpenJDK 64-Bit Server VM (build 25.392-b08, mixed mode)

[root@132 /]# mkdir /apps
[root@132 ~]# tar xvf Mycat-server-1.6.7.6-release-20210303094759-linux.tar.gz -C /apps
root@132 ~]# ls /apps/mycat/
bin  catlet  conf  lib  logs  version.txt

2.配置mycat环境变量

[root@132 ~]# echo 'PATH=/apps/mycat/bin:$PATH' > /etc/profile.d/mycat.sh
[root@132 ~]# source /etc/profile.d/mycat.sh
[root@132 ~]# ss -ntl
State       Recv-Q      Send-Q           Local Address:Port           Peer Address:Port      Process      
LISTEN      0           128                    0.0.0.0:22                  0.0.0.0:*                      
LISTEN      0           128                       [::]:22                     [::]:*

3.启动mycat

[root@132 ~]# file /apps/mycat/bin/mycat
/apps/mycat/bin/mycat: POSIX shell script, ASCII text executable
[root@132 ~]# mycat
Usage: /apps/mycat/bin/mycat { console | start | stop | restart | status | dump }
[root@132 ~]# mycat start
Starting Mycat-server...
[root@132 ~]# ss -ntl
State       Recv-Q      Send-Q           Local Address:Port            Peer Address:Port     Process      
LISTEN      0           128                    0.0.0.0:22                   0.0.0.0:*                     
LISTEN      0           1                    127.0.0.1:32000                0.0.0.0:*                     
LISTEN      0           128                          *:9066                       *:*                     
LISTEN      0           50                           *:33941                      *:*                     
LISTEN      0           128                       [::]:22                      [::]:*                     
LISTEN      0           50                           *:1984                       *:*                     
LISTEN      0           50                           *:33505                      *:*                     
LISTEN      0           128                          *:8066                       *:*                     
[root@132 ~]# #tail /apps/mycat/logs/wrapper.log
[root@132 ~]# tail /apps/mycat/logs/wrapper.log
STATUS | wrapper  | 2024/01/07 13:34:38 | --> Wrapper Started as Daemon
STATUS | wrapper  | 2024/01/07 13:34:38 | Launching a JVM...
INFO   | jvm 1    | 2024/01/07 13:34:38 | Wrapper (Version 3.2.3) http://wrapper.tanukisoftware.org
INFO   | jvm 1    | 2024/01/07 13:34:38 |   Copyright 1999-2006 Tanuki Software, Inc.  All Rights Reserved.
INFO   | jvm 1    | 2024/01/07 13:34:38 | 
INFO   | jvm 1    | 2024/01/07 13:34:41 | MyCAT Server startup successfully. see logs in logs/mycat.log

4.链接mycat

[root@132 ~]# mysql -uroot -p123456 -h 192.168.29.132 -P8066
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.6.29-mycat-1.6.7.6-release-20210303094759 MyCat Server (OpenCloudDB)

Copyright (c) 2000, 2023, Oracle and/or its affiliates.

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 databases;
+----------+
| DATABASE |
+----------+
| TESTDB   |
+----------+
1 row in set (0.00 sec)

修改mycat配置文件

1.修改mycat 端口号将默认的8066改为3306

[root@132 ~]# vim /apps/mycat/conf/server.xml
   <property name="processorBufferPoolType">0</property>
                <property name="serverPort">3306</property
[root@132 ~]# mycat restart
Stopping Mycat-server...
Stopped Mycat-server.
Starting Mycat-server...
[root@132 ~]# ss -ntl
State       Recv-Q      Send-Q           Local Address:Port            Peer Address:Port     Process      
LISTEN      0           128                    0.0.0.0:22                   0.0.0.0:*                     
LISTEN      0           1                    127.0.0.1:32000                0.0.0.0:*                     
LISTEN      0           128                          *:3306                       *:*                     
LISTEN      0           128                          *:9066                       *:*                     
LISTEN      0           50                           *:44819                      *:*                     
LISTEN      0           128                       [::]:22                      [::]:*                     
LISTEN      0           50                           *:1984                       *:*                     
LISTEN      0           50                           *:37409                      *:*

2.配置master131 创建mycat映射账号并授权

mysql> create user 'mycat'@'192.168.29.%' identified by '123456';
Query OK, 0 rows affected (0.01 sec)

mysql> grant all on hellodb.* to 'mycat'@'192.168.29.%';
Query OK, 0 rows affected (0.00 sec)

3.修改mycat132 schema 映射配置

[root@132 ~]# cat schema.xml 
<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="http://io.mycat/">
    <schema name="TESTDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="dn1">
    </schema>
    <dataNode name="dn1" dataHost="localhost1" database="hellodb" />
    <dataHost name="localhost1" maxCon="1000" minCon="10" balance="1"
              writeType="0" dbType="mysql" dbDriver="native" switchType="1"  slaveThreshold="100">
        <heartbeat>select user()</heartbeat>
        <writeHost host="host1" url="192.168.29.131:3306" user="mycat" password="123456">       #master 131
         <readHost host="host2" url="192.168.29.130:3306" user="mycat" password="123456" />    #slave 130
        </writeHost>
    </dataHost>
</mycat:schema>

验证mycat

1.master 131和 slave 130开启通用日志

[root@131 ~]# cat /etc/my.cnf
#
# This group is read both both by the client and the server
# use it for options that affect everything
#
[client-server]

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d
[client]
user=root
password=123456
[mysqld]
server-id=131
log-bin= /data/mysql/log/mysql-bin
general_log
[root@131 ~]# systemctl restart mysqld

[root@130 /]# cat /etc/my.cnf
#
# This group is read both both by the client and the server
# use it for options that affect everything
#
[client-server]

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d
[client]
user=root
password=123456
[mysqld]
server_id=130
log-bin = /data/mysql/log/mysql.bin
#read_only=ON
general_log
[root@130 /]# systemctl restart mysqld

2.在mycat132上查询和修改：

mysql> select * from  teachers;
+-----+---------------+-----+--------+
| TID | Name          | Age | Gender |
+-----+---------------+-----+--------+
|   1 | Song Jiang    |  45 | M      |
|   2 | Zhang Sanfeng |  94 | M      |
|   3 | Miejue Shitai |  77 | F      |
|   4 | Lin Chaoying  |  93 | F      |
+-----+---------------+-----+--------+
4 rows in set (0.00 sec)

mysql> update teachers set age=60 where TID=1;
Query OK, 1 row affected (0.01 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select * from  teachers;
+-----+---------------+-----+--------+
| TID | Name          | Age | Gender |
+-----+---------------+-----+--------+
|   1 | Song Jiang    |  60 | M      |
|   2 | Zhang Sanfeng |  94 | M      |
|   3 | Miejue Shitai |  77 | F      |
|   4 | Lin Chaoying  |  93 | F      |
+-----+---------------+-----+--------+
4 rows in set (0.00 sec)

3.分别在master131和slave130的通用日志上比较

[root@131 ~]# cat /var/lib/mysql/131.log 
2024-01-07T07:03:59.325794Z     8 Query select user()
2024-01-07T07:04:08.356940Z    10 Query update teachers set age=60 where TID=1
2024-01-07T07:04:09.318810Z    12 Query select user()
2024-01-07T07:04:19.322645Z    11 Query select user()

[root@130 /]# cat /var/lib/mysql/130.log
2024-01-07T07:04:09.327203Z    14 Query select user()
2024-01-07T07:04:13.258357Z    17 Query select * from  teachers
2024-01-07T07:04:19.330838Z    16 Query select user()

结论mycat实现读写分离成功

6. 实现openvpn部署，并且测试通过，输出博客或者自己的文档存档。

环境配置共4台主机

openvpn eth0NAT模式:192.168.29.130 eth1仅主机模式:192.168.87.128
web1仅主机模式: 192.168.87.129
web2仅主机模式: 192.168.87.130
windows11

7、mysql如何实现崩溃后恢复？

MySQL数据库在崩溃后可以通过以下几种方式来实现恢复：

  1.启用二进制日志（Binary Log）：MySQL提供了二进制日志功能，它记录了所有数据库操作语句的日志。在崩溃后，可以使用二进制日志进行恢复。需要确保在MySQL配置文件中启用了二进制日志，并定期备份二进制日志文件。

  2.使用事务日志（InnoDB存储引擎）：如果使用的是InnoDB存储引擎，它提供了事务日志（也称为重做日志）功能。事务日志记录了正在进行中的事务操作，包括对表的修改。在崩溃后，MySQL可以使用事务日志进行恢复。

  3.备份与恢复：定期备份MySQL数据库是非常重要的。使用数据库备份工具，如mysqldump命令行工具或第三方xtrabackup备份工具，可以将数据库备份到另一个存储位置。在崩溃后，可以使用备份文件来还原数据库。

  4.使用故障转移与复制功能：MySQL支持主从复制和主主复制功能。通过设置主从复制或主主复制，可以将数据复制到多个服务器上。当主服务器崩溃时，可以使用其中一个从服务器继续提供服务。

8、myisam和innodb各自在什么场景使用？

MyISAM和InnoDB是MySQL数据库中两种常见的存储引擎。

MyISAM适用于以下场景：

  对于读密集型应用：MyISAM在处理大量的SELECT操作时性能较好，因为它使用了表级锁定而不是行级锁定，这意味着在读取数据时不会出现锁冲突。

  需要全文搜索功能：MyISAM支持全文索引，使得在文本数据上进行高效的全文搜索成为可能。

  插入和查询的比例较低：由于MyISAM会在执行写操作时锁定整个表，所以在插入和查询的比例较低的应用中，效果更好。

InnoDB适用于以下场景：

  对于写密集型应用：InnoDB在处理大量的INSERT和UPDATE操作时性能较好，因为它使用了行级别的锁定，可以避免锁冲突，提高并发性能。

  需要事务支持：InnoDB是MySQL的默认事务存储引擎，支持ACID（原子性、一致性、隔离性和持久性）事务，可以确保数据的完整性和一致性。

  强调数据的安全性：InnoDB支持外键约束和崩溃恢复机制，可以保证数据的安全性和稳定性。
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