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mysql完全備份與mysql增量備份相搭配
多點異地備份

關於數據庫備份方案

冷備份

場景：
一般主要用於非核心業務，這類業務一般都是允許業務中斷的，冷備份的特點就是數度快，恢復時也最爲簡單。通常直接復物理文件來實現冷備份
缺點：

需要停止MySQL服務。
僅支持在完全相同版本的mysql服務之間實現數據備份、轉移、恢復
完全備份（全部數據庫的全部數據），數據量大時不方便。

實現方法

備份前的數據

# 以fafamcu數據庫爲例演示
root@ubuntu:/var/lib/mysql# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 50
Server version: 5.5.55-0ubuntu0.14.04.1 (Ubuntu)

Copyright (c) 2000, 2017, 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.

Database changed
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| fafamcu            |
| mysql              |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)

mysql> use fafamcu;
Database changed
mysql> show tables;
+-------------------+
| Tables_in_fafamcu |
+-------------------+
| mcuidx            |
| mculist           |
| mcuroom           |
| meet              |
| meetTimeRecord    |
| netinfo           |
| user              |
+-------------------+
7 rows in set (0.00 sec)

mysql> select * from mcuidx;
+----+---------+
| id | idx     |
+----+---------+
|  1 |  112123 |
|  2 | 1122334 |
|  3 |  112233 |
+----+---------+
3 rows in set (0.00 sec)

mysql> quit
Bye

進行數據備份

# 查看數據存放路徑
root@ubuntu:/var/lib/mysql# vim /etc/mysql/my.cnf 
    [mysqld]
    datadir         = /var/lib/mysql
# 直接對數據路徑進行打包即可
root@ubuntu:/var/lib/mysql# cd ..
root@ubuntu:/var/lib# tar -zcPf mysql.tar.gz mysql/*
root@ubuntu:/var/lib# ls mysql
debian-5.5.flag  fafamcu  ibdata1  ib_logfile0  ib_logfile1  mysql  mysql_upgrade_info  performance_schema

模擬誤刪數據庫

root@ubuntu:/var/lib# mysql -uroot -p
Enter password: 
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
root@ubuntu:/var/lib# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 52
Server version: 5.5.55-0ubuntu0.14.04.1 (Ubuntu)

Copyright (c) 2000, 2017, 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 databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| fafamcu            |
| mysql              |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)

mysql> drop databases fafamcu;
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 'databases fafamcu' at line 1
mysql> drop database fafamcu;
Query OK, 7 rows affected (0.01 sec)

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

mysql> quit
Bye

進行數據恢復

# 停止mysql服務
root@ubuntu:/var/lib# service  mysql stop 
mysql stop/waiting
root@ubuntu:/var/lib# netstat -anlp| grep :3306
# 轉移舊數據目錄
root@ubuntu:/var/lib# mv mysql  mysql-err
# 恢復備份的數據目錄
root@ubuntu:/var/lib# tar -xf mysql.tar.gz 
root@ubuntu:/var/lib# ls mysql
debian-5.5.flag  fafamcu  ibdata1  ib_logfile0  ib_logfile1  mysql  mysql_upgrade_info  performance_schema
root@ubuntu:/var/lib# service  mysql start
mysql start/running, process 2564
root@ubuntu:/var/lib# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 38
Server version: 5.5.55-0ubuntu0.14.04.1 (Ubuntu)

Copyright (c) 2000, 2017, 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 databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| fafamcu            |
| mysql              |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)

mysql> use fafamcu;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> show tables;
+-------------------+
| Tables_in_fafamcu |
+-------------------+
| mcuidx            |
| mculist           |
| mcuroom           |
| meet              |
| meetTimeRecord    |
| netinfo           |
| user              |
+-------------------+
7 rows in set (0.00 sec)

mysql> select * from mcuidx;
+----+---------+
| id | idx     |
+----+---------+
|  1 |  112123 |
|  2 | 1122334 |
|  3 |  112233 |
+----+---------+
3 rows in set (0.00 sec)

熱備份

邏輯備份

缺點：

消耗服務器資源，會對服務器造成壓力
當數據量較大時（1G時就很明顯了），備份及恢復速度慢慢慢

實現方法

備份前的數據

root@ubuntu:/var/lib# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 39
Server version: 5.5.55-0ubuntu0.14.04.1 (Ubuntu)

Copyright (c) 2000, 2017, 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 databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| fafamcu            |
| mysql              |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)

mysql> use fafamcu;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> show tables;
+-------------------+
| Tables_in_fafamcu |
+-------------------+
| mcuidx            |
| mculist           |
| mcuroom           |
| meet              |
| meetTimeRecord    |
| netinfo           |
| user              |
+-------------------+
7 rows in set (0.00 sec)

mysql> select * from mcuidx;
+----+---------+
| id | idx     |
+----+---------+
|  1 |  112123 |
|  2 | 1122334 |
|  3 |  112233 |
+----+---------+
3 rows in set (0.00 sec)

mysql> quit
Bye

進行數據備份

root@ubuntu:/var/lib# mysqldump -uroot -p fafamcu --default-character-set=utf8 --opt -Q -R --skip-lock-tables> fafamcu.sql
Enter password: 
root@ubuntu:/var/lib# ls fafamcu.sql 
fafamcu.sql

模擬誤刪數據庫

root@ubuntu:/var/lib# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 43
Server version: 5.5.55-0ubuntu0.14.04.1 (Ubuntu)

Copyright (c) 2000, 2017, 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 databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| fafamcu            |
| mysql              |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)

mysql> drop database fafamcu;
Query OK, 0 rows affected (0.00 sec)

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

mysql> quit
Bye

進行數據恢復

# 提前創建數據庫
root@ubuntu:/var/lib# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 44
Server version: 5.5.55-0ubuntu0.14.04.1 (Ubuntu)

Copyright (c) 2000, 2017, 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> create database fafamcu;
Query OK, 1 row affected (0.00 sec)

mysql> quit
Bye
# 導入數據庫
root@ubuntu:/var/lib# mysql -uroot -p fafamcu < fafamcu.sql 
Enter password: 
root@ubuntu:/var/lib# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 46
Server version: 5.5.55-0ubuntu0.14.04.1 (Ubuntu)

Copyright (c) 2000, 2017, 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 databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| fafamcu            |
| mysql              |
| performance_schema |
+--------------------+
4 rows in set (0.00 sec)

mysql> use fafamcu
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> show tables;
+-------------------+
| Tables_in_fafamcu |
+-------------------+
| mcuidx            |
| mculist           |
| mcuroom           |
| meet              |
| meetTimeRecord    |
| netinfo           |
| user              |
+-------------------+
7 rows in set (0.00 sec)

mysql> select * from mcuidx;
+----+---------+
| id | idx     |
+----+---------+
|  1 |  112123 |
|  2 | 1122334 |
|  3 |  112233 |
+----+---------+
3 rows in set (0.00 sec)

一個參考腳本

#!/bin/bash
#使用：./xx.sh -uroot -p'123456'，使用前修改腳本進行變量配置
#過程：備份並刷新binlog，將最新的binlog文件名記錄並整體壓縮打包
#恢復：先進行全量備份，再對根據tim-binlog.txt中的記錄，進行逐個恢復
#提示：最多每分鐘執行一次，否則會覆蓋同分鍾內的文件，可以修改腳本來改善
#      出現問題會退出，可以到指定的日誌目錄查看日誌輸出
#      同年的tar包超過指定天數的會刪除掉

#[變量]
begin_time=`date +%F-%H-%M-%S`
my_sql="/usr/local/mysql/bin/mysql"
bak_sql="/usr/local/mysql/bin/mysqldump"
binlog_dir=/data/mysql/
bak_dir=/ops/bak
log_dir=/ops/log/mybak-all.log
#保存的天數，4周就是28天
save_day=28

#[自動變量]
#當前年月
date_nian=`date +%Y-`
#所有天數的數組
save_day_zu=($(for i in `seq 1 ${save_day}`;do date -d -${i}days "+%F";done))

#開始
/usr/bin/echo >> ${log_dir}
/usr/bin/echo "time:$(date +%F-%H-%M-%S) info:開始全備份" >> ${log_dir}

#檢查
${my_sql} $* -e "show databases;" &> /tmp/info_error.txt
if [[ $? -ne 0 ]];then
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) info:登陸命令錯誤" >> ${log_dir}
    /usr/bin/cat /tmp/info_error.txt #如果錯誤則顯示錯誤信息
    exit 1
fi

#移動到目錄
cd ${bak_dir}
bak_time=`date +%F-%H-%M`
bak_timetwo=`date +%F`

#備份
${bak_sql} $* --all-databases --flush-privileges --single-transaction --flush-logs --triggers --routines --events --hex-blob > mybak-all-${bak_time}.sql
if [[ $? -ne 0 ]];then
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) error:備份失敗"
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) error:備份失敗" >> ${log_dir}
    /usr/bin/cat /tmp/bak_error.txt #如果錯誤則顯示錯誤信息
    exit 1
else
    bin_dian=`tail -n 1 ${binlog_dir}/mysql-bin.index`
    echo "${bin_dian}" > ${bak_time}-binlog.txt
fi

#壓縮
if [[ -f mybak-all-${bak_time}.tar.gz ]];then
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) info:壓縮包mybak-section-${bak_time}.tar.gz 已存在" >> ${log_dir}
    /usr/bin/rm -irf mybak-all-${bak_time}.tar.gz ${bak_sql}-binlog.txt
fi
/usr/bin/tar -cf mybak-all-${bak_time}.tar.gz mybak-all-${bak_time}.sql ${bak_time}-binlog.txt
if [[ $? -ne 0 ]];then
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) error:壓縮失敗" >> ${log_dir}
    exit 1
fi

#刪除sql文件
/usr/bin/rm -irf mybak-all-${bak_time}.sql ${bak_time}-binlog.txt
if [[ $? -ne 0 ]];then
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) info:刪除sql文件失敗" >> ${log_dir}
    exit 1
fi

#整理壓縮的日誌文件
for i in `ls | grep .tar.gz$`
   do
    echo $i | grep "^mybak-all.*tar.gz$" &> /dev/null
        if [[ $? -eq 0 ]];then
            a=`echo ${i%%.tar.gz}`
            b=`echo ${a:(-16)}`
            c=`echo ${b%-*}`
            d=`echo ${c%-*}`
            #看是否在數組中，不在則刪除
            echo ${save_day_zu[*]} |grep -w $d &> /dev/null
            if [[ $? -ne 0 ]];then
                [[ "$d" != "$bak_timetwo" ]] && rm -rf $i
            fi
        else
            #不是當月的，其他類型壓縮包，跳過
            continue
        fi
done

#結束
last_time=`date +%F-%H-%M-%S`
/usr/bin/echo "begin_time:${begin_time}   last_time:${last_time}" >> ${log_dir}
/usr/bin/echo "time:$(date +%F-%H-%M-%S) info:全備份完成" >> ${log_dir}
/usr/bin/echo >> ${log_dir}

差量備份

增量備份

一個參考腳本

#!/bin/bash
#使用：./xx.sh -uroot -p'123456'，將第一次增量備份後的binlog文件名寫到/tmp/binlog-section中，若都沒有，自動填寫mysql-bin.000001
#過程：增量先刷新binlog日誌，再查詢/tmp/binlog-section中記錄的上一次備份中最新的binlog日誌的值
#      cp中間的binlog日誌，並進行壓縮。再將備份中最新的binlog日誌寫入。

#恢復：先進行全量恢復，再根據全量備份附帶的time-binlog.txt中的記錄逐個恢復。當前最新的Binlog日誌要去掉有問題的語句，例如drop等。
#提示：最多每分鐘執行一次，否則會覆蓋同分鍾內的文件，可以修改腳本來改善
#      出現問題會退出，可以到指定的日誌目錄查看日誌輸出
#      同年的tar包超過指定天數的會刪除掉

#[變量]
begin_time=`date +%F-%H-%M-%S`
my_sql="/usr/local/mysql/bin/mysql"
bak_sql="/usr/local/mysql/bin/mysqldump"
binlog_dir=/data/mysql/
binlog_index=${binlog_dir}/mysql-bin.index
bak_dir=/ops/bak
log_dir=/ops/log/mybak-section.log
#保存的天數，4周就是28天
save_day=7

#[自動變量]
#當前年
date_nian=`date +%Y-`
#所有天數的數組
save_day_zu=($(for i in `seq 1 ${save_day}`;do date -d -${i}days "+%F";done))


#開始
/usr/bin/echo >> ${log_dir}
/usr/bin/echo "time:$(date +%F-%H-%M-%S) info:開始增量備份" >> ${log_dir}

#檢查
${my_sql} $* -e "show databases;" &> /tmp/info_error.txt
if [[ $? -ne 0 ]];then
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) info:登陸命令錯誤" >> ${log_dir}
    /usr/bin/cat /tmp/info_error.txt #如果錯誤則顯示錯誤信息
    exit 1
fi

#移動到目錄
cd ${bak_dir}
bak_time=`date +%F-%H-%M`
bak_timetwo=`date +%F`

#刷新
${my_sql} $* -e "flush logs"
if [[ $? -ne 0 ]];then
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) error:刷新binlog失敗" >> ${log_dir}
    exit 1
fi

#獲取開頭和結尾binlog名字
last_bin=`cat /tmp/binlog-section`
next_bin=`tail -n 1 ${binlog_dir}/mysql-bin.index`
echo ${last_bin} |grep 'mysql-bin' &> /dev/null
if [[ $? -ne 0 ]];then
    echo "mysql-bin.000001" > /tmp/binlog-section #不存在則默認第一個
    last_bin=`cat /tmp/binlog-section`
fi

#截取需要備份的binlog行數
a=`/usr/bin/sort ${binlog_dir}/mysql-bin.index | uniq | grep -n ${last_bin} | awk -F':' '{print $1}'`
b=`/usr/bin/sort ${binlog_dir}/mysql-bin.index | uniq | grep -n ${next_bin} | awk -F':' '{print $1}'`
let b--

#輸出最新節點
/usr/bin/echo "${next_bin}" > /tmp/binlog-section

#創建文件
rm -rf mybak-section-${bak_time}
/usr/bin/mkdir mybak-section-${bak_time}
for i in `sed -n "${a},${b}p" ${binlog_dir}/mysql-bin.index  | awk -F'./' '{print $2}'`
do
    if [[ ! -f ${binlog_dir}/${i} ]];then
        /usr/bin/echo "time:$(date +%F-%H-%M-%S) error:binlog文件${i} 不存在" >> ${log_dir}
        exit 1
    fi
    cp -rf ${binlog_dir}/${i} mybak-section-${bak_time}/
    if [[ ! -f mybak-section-${bak_time}/${i} ]];then
        /usr/bin/echo "time:$(date +%F-%H-%M-%S) error:binlog文件${i} 備份失敗" >> ${log_dir}
        exit 1
    fi
done

#壓縮
if [[ -f mybak-section-${bak_time}.tar.gz ]];then
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) info:壓縮包mybak-section-${bak_time}.tar.gz 已存在" >> ${log_dir}
    /usr/bin/rm -irf mybak-section-${bak_time}.tar.gz
fi


/usr/bin/tar -cf mybak-section-${bak_time}.tar.gz mybak-section-${bak_time}
if [[ $? -ne 0 ]];then
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) error:壓縮失敗" >> ${log_dir}
    exit 1
fi

#刪除binlog文件夾
/usr/bin/rm -irf mybak-section-${bak_time}
if [[ $? -ne 0 ]];then
    /usr/bin/echo "time:$(date +%F-%H-%M-%S) info:刪除sql文件失敗" >> ${log_dir}
    exit 1
fi

#整理壓縮的日誌文件
for i in `ls | grep "^mybak-section.*tar.gz$"`
   do
    echo $i | grep ${date_nian} &> /dev/null
        if [[ $? -eq 0 ]];then
            a=`echo ${i%%.tar.gz}`
            b=`echo ${a:(-16)}` #當前日誌年月日
            c=`echo ${b%-*}`
            d=`echo ${c%-*}`
 
            #看是否在數組中，不在其中，並且不是當前時間，則刪除。
            echo ${save_day_zu[*]} |grep -w $d &> /dev/null
            if [[ $? -ne 0 ]];then
                [[ "$d" != "$bak_timetwo" ]] && rm -rf $i
            fi
        else
            #不是當月的，其他類型壓縮包，跳過
            continue
        fi
done

#結束
last_time=`date +%F-%H-%M-%S`
/usr/bin/echo "begin_time:${begin_time}   last_time:${last_time}" >> ${log_dir}
/usr/bin/echo "time:$(date +%F-%H-%M-%S) info:增量備份完成" >> ${log_dir}
/usr/bin/echo >> ${log_dir}

# 週六晚3點i分進行全量備份 週一到週六每天進行增量備份， 全量保存4周 增量保存近一週的每天數據
crontab -e 添加計劃任務。
    1 3 * * 6 /bin/bash /shell/mybak-all.sh -uroot -p'123456'
    1 2 * * * /bin/bash /shell/mybak-section.sh -uroot -p'123456'

參考地址：
https://blog.csdn.net/weixin_34032779/article/details/93204960

實現方法

備份前數據

# 進行一次完全備份，基於完全備份按順序執行之後二進制日誌可進行數據的恢復。
root@ubuntu:/var/log/mysql# mysqldump -uroot -p fafamcu --default-character-set=utf8 --opt -Q -R --skip-lock-tables> fafamcu.sql
Enter password: 
root@ubuntu:/var/log/mysql# ls
error.log  fafamcu.sql  mysql-bin.000001  mysql-bin.000002  mysql-bin.000003  mysql-bin.000004  mysql-bin.index
root@ubuntu:/var/log/mysql# mysqladmin -uroot -p flush-logs
Enter password: 
root@ubuntu:/var/log/mysql# ls
error.log  fafamcu.sql  mysql-bin.000001  mysql-bin.000002  mysql-bin.000003  mysql-bin.000004  mysql-bin.000005  mysql-bin.index
root@ubuntu:/var/log/mysql# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 51
Server version: 5.5.55-0ubuntu0.14.04.1-log (Ubuntu)

Copyright (c) 2000, 2017, 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> use fafamcu
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> select * from mcuidx;
+----+---------+
| id | idx     |
+----+---------+
|  1 |  112123 |
|  2 | 1122334 |
|  3 |  112233 |
|  4 |  200619 |
+----+---------+
4 rows in set (0.00 sec)

模擬第一次增量備份

# 增加數據
mysql> insert into mcuidx values (5.200620);
ERROR 1136 (21S01): Column count doesn't match value count at row 1
mysql> insert into mcuidx values (5,200620);
Query OK, 1 row affected (1.60 sec)

mysql> select * from mcuidx;
+----+---------+
| id | idx     |
+----+---------+
|  1 |  112123 |
|  2 | 1122334 |
|  3 |  112233 |
|  4 |  200619 |
|  5 |  200620 |
+----+---------+
5 rows in set (0.00 sec)

mysql> quit
Bye

模擬第二次增量備份

# 生成新的二進制日誌文件
root@ubuntu:/var/log/mysql# mysqladmin -uroot -p flush-logs
Enter password: 
root@ubuntu:/var/log/mysql# ls
error.log  fafamcu.sql  mysql-bin.000001  mysql-bin.000002  mysql-bin.000003  mysql-bin.000004  mysql-bin.000005  mysql-bin.000006  mysql-bin.index
# 模式失誤刪除數據
root@ubuntu:/var/log/mysql# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 53
Server version: 5.5.55-0ubuntu0.14.04.1-log (Ubuntu)

Copyright (c) 2000, 2017, 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> use fafamcu
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> select * from mcuidx;
+----+---------+
| id | idx     |
+----+---------+
|  1 |  112123 |
|  2 | 1122334 |
|  3 |  112233 |
|  4 |  200619 |
|  5 |  200620 |
+----+---------+
5 rows in set (0.00 sec)

mysql> delete from mcuidx where id=1;
Query OK, 1 row affected (0.00 sec)

mysql> delete from mcuidx where id=2;
Query OK, 1 row affected (0.01 sec)

mysql> select * from mcuidx;
+----+--------+
| id | idx    |
+----+--------+
|  3 | 112233 |
|  4 | 200619 |
|  5 | 200620 |
+----+--------+
3 rows in set (0.00 sec)

mysql> quit
Bye

進行數據恢復

# 恢復完全備份
root@ubuntu:/var/log/mysql# mysql -uroot -p fafamcu < fafamcu.sql 
Enter password: 
root@ubuntu:/var/log/mysql# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 55
Server version: 5.5.55-0ubuntu0.14.04.1-log (Ubuntu)

Copyright (c) 2000, 2017, 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> use fafamcu;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> select * from mcudix;
ERROR 1146 (42S02): Table 'fafamcu.mcudix' doesn't exist
mysql> show tables;
+-------------------+
| Tables_in_fafamcu |
+-------------------+
| mcuidx            |
| mculist           |
| mcuroom           |
| meet              |
| meetTimeRecord    |
| netinfo           |
| user              |
+-------------------+
7 rows in set (0.00 sec)

mysql> select * from mcuidx;
+----+---------+
| id | idx     |
+----+---------+
|  1 |  112123 |
|  2 | 1122334 |
|  3 |  112233 |
|  4 |  200619 |
+----+---------+
4 rows in set (0.00 sec)

mysql> quit
Bye

使用二進制日誌恢復數據

# 使用第一次增量備份產生的二進制日誌恢復第一部分數據
root@ubuntu:/var/log/mysql# ls
error.log  fafamcu.sql  mysql-bin.000001  mysql-bin.000002  mysql-bin.000003  mysql-bin.000004  mysql-bin.000005  mysql-bin.000006  mysql-bin.index
root@ubuntu:/var/log/mysql# mysqlbinlog  --no-defaults mysql-bin.000005 | mysql -uroot -p
Enter password: 
root@ubuntu:/var/log/mysql# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 58
Server version: 5.5.55-0ubuntu0.14.04.1-log (Ubuntu)

Copyright (c) 2000, 2017, 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> use fafamcu;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> select * from mcuidx;
+----+---------+
| id | idx     |
+----+---------+
|  1 |  112123 |
|  2 | 1122334 |
|  3 |  112233 |
|  4 |  200619 |
|  5 |  200620 |
+----+---------+
5 rows in set (0.00 sec)

關於數據庫容災方案

關於數據庫守護方案

關於數據庫（1T）備份、還原方案

https://blog.csdn.net/yincg/article/details/71409502

關於數據庫備份

參考地址1（推薦，如何實現mysql的1T數據庫備份）：
https://blog.csdn.net/enweitech/article/details/51612858?utm_medium=distribute.pc_relevant.none-task-blog-BlogCommendFromMachineLearnPai2-1.nonecase&depth_1-utm_source=distribute.pc_relevant.none-task-blog-BlogCommendFromMachineLearnPai2-1.nonecase
參考地址2：
https://blog.csdn.net/longyuhome/article/details/35786487/

關於性能優化

架構優化

1、選擇爭取的存儲引擎
InnoDB支持事務，大量的insert update用它，count需要掃描整個表，提供行鎖，支持外鍵，主鍵
範圍大
MyISAM執行速度看性能高，大量的select用它，表鎖，支持全文索引支持GIS數據
2、視圖
3、字段類型
4、不要是使用null
5、有固定的值用emum
6、爲每張表設置一個ID作爲主鍵，並且自增
7、使用索引
8、-static 連接的話，MySQL執行速度的速度是最快的

查找技巧優化

1、拆分大的delete insert語句
2、不要用select *
3、不要order by rand

配置文件優化

1、慢查詢 slow_qurey_log
2、物理內存越大,設置就越大.默認爲2402,調到512-1024最佳
innodb_additional_mem_pool_size=4M
3、指定MySQL允許的最大連接進程數。如果在訪問論壇時經常出現Too Many Connection(www.111cn.net)s的錯
誤提示，則需要增大該參數值。
max_connect_errors = 1000000
4、指定MySQL查詢緩衝區的大小
tmp_table_size = 256M

發現問題優化

PHP查詢數據庫慢？

問題現象：
通過測試得出:服務器執行php文件速度正常，從MySQL數據庫讀取數據速度異常。進一步測試發現，MySQL -uroot -p -h 12.0.2.49過程緩慢。
解決方法：
更改MySQL配置文件my.cnf，添加以下代碼:
[mysqld]
skip-name-resolve #Don’t resolve hostnames
重啓MySQL服務即可。
問題總結：
服務器做了一個本地dns服務，每次執行訪問DB數據庫操作時，MySQL就會試圖去解析來訪問的機器的domain name，如果這時解析不成功，等一段時間會失敗，數據才能被取過來。

mysql服務器頻繁掛掉（down）&&CPU高

問題現象：
公司網站剛改完版,優化了數據庫結構,使用的memcache分佈式緩存加mysql,剛開始幾天還好,數據庫服務幾天沒down過了.但這幾天頻繁down機.是個大問題,需要解決.
問題分析：

確保服務器硬件配置是合理的
查看服務器負載(top命令),見mysql竟然經常百分之九十幾的cpu,恐怖.早之前就知道,數據表有些字段沒有做索引的,引起MYSQL負載這麼高的原因主要應該是索引問題和某些變態SQL語句.

如何知道是MYSQL哪些索引和SQL引起的問題呢?老大教有絕招
解決方法：
編輯MYSQL配置文件my.cnf,加上以下幾行:
log_slow_queries=/usr/local/mysql/data/log_slow_queries.log //慢語句日誌保存目錄
long_query_time=10 //記錄SQL查詢超過10S的語句
log-queries-not-using-indexes=1 //記錄沒有使用索引的sql

這樣,慢語句就被記錄在日誌文件中了.
tail -f /usr/local/mysql/data/log_slow_queries.log 查看日誌.
四個參數
Query_time: 0 Lock_time: 0 Rows_sent: 1 Rows_examined: 54
分別意思爲:查詢時間鎖定時間查詢結果行數掃描行數
主要看那些掃描行數超多的語句.然後去數據庫加上對應的索引
再優化下變態的sql
完成後mysql負載降到了二十幾.還行.應該不會down機了.

Mysql 高負載排查思路

問題描述：
top命令查看服務器負載,發現 mysql竟然百分之兩百的cpu,引起Mysql 負載這麼高的原因,估計是索引問題和某些變態SQL語句.

排查思路：

確定高負載的類型,top命令看負載高是CPU還是IO。
mysql 下執行查看當前的連接數與執行的sql 語句。
檢查慢查詢日誌，可能是慢查詢引起負載高。
檢查硬件問題，是否磁盤故障問題造成的。
檢查監控平臺，對比此機器不同時間的負載。

確定負載類型(top)

top - 10:14:18 up 23 days, 11:01,  1 user, load average: 124.17, 55.88, 24.70 Tasks: 138 total,   1 running, 137 sleeping,   0 stopped,   0 zombie Cpu(s):  2.4%us,  1.0%sy,  0.0%ni, 95.2%id,  2.0%wa,  0.1%hi,  0.2%si,  0.0%st Mem:   3090528k total,  2965772k used,   124756k free,    93332k buffers Swap:  4192956k total,  2425132k used,  1767824k free,   756524k cached            PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND 30833 mysql     15   0 6250m 2.5g 4076 S 257.1 49.9 529:34.45 mysqld

查看當前的連接數與執行的sql 語句

>show processlist; 
Id  User    Host    db  Command Time    State   Info 192 slave   8.8.8.142:39820 NULL    Binlog Dump 58982   Has sent all binlog to slave;
waiting for binlog to be updated  NULL 194 slave   8.8.8.120:41075 NULL    Binlog Dump 58982   Has sent all binlog to slave; 
waiting for binlog to be updated  NULL 424891 biotherm    8.8.8.46:57861  biotherm    Query   493 Sending data    
>SELECT * FROM xxx_list WHERE tid = '1112'  AND del = 0  ORDER BY  id DESC  LIMIT 0, 4 
424917 biotherm    8.8.8.49:50984  biotherm    Query   488 Sending data   
>SELECT * FROM xxx_list WHERE tid = '1112'  AND del = 0  ORDER BY  id DESC  LIMIT 0, 4 
430330 biotherm    8.8.8.42:35982  biotherm    Query   487 Sending data    
>SELECT * FROM xxx_list WHERE tid = '1112'  AND del = 0

記錄慢查詢
編輯Mysql 配置文件(my.cnf),在[mysqld]字段添加以下幾行:
log_slow_queries = /usr/local/mysql/var/slow_queries.log #慢查詢日誌路徑
long_query_time = 10 #記錄SQL查詢超過10s的語句
log-queries-not-using-indexes = 1 #記錄沒有使用索引的sql

查看慢查詢日誌

tail /usr/local/mysql/var/slow_queries.log 
# Time: 130305  9:48:13 # User@Host: biotherm[biotherm] @  [8.8.8.45] 
# Query_time: 1294.881407  Lock_time: 0.000179 Rows_sent: 4  Rows_examined: 1318033 SET timestamp=1363916893; SELECT * FROM xxx_list WHERE tid = '11xx'  AND del = 0  ORDER BY  id DESC  LIMIT 0, 4;

4個參數
Query_time: 0 Lock_time: 0 Rows_sent: 1 Rows_examined: 54
分別意思爲:查詢時間鎖定時間查詢結果行數掃描行數
主要看掃描行數多的語句,然後去數據庫加上對應的索引,再優化下變態的sql 語句。

極端情況kill sql進程
找出佔用cpu時間過長的sql，在mysql 下執行如下命令： show processlist; 確定後一條sql處於Query狀態，且Time時間過長，鎖定它的ID，執行如下命令： kill QUERY 269815764;
注意：殺死 sql進程，可能導致數據丟失，所以執行前要衡量數據的重要性。

修改mysql密碼

1．首先確認服務器出於安全的狀態，也就是沒有人能夠任意地連接MySQL數據庫。
因爲在重新設置MySQL的root密碼的期間，MySQL數據庫完全出於沒有密碼保護的狀態下，其他的用戶也可以任意地登錄和修改MySQL的信息。可以採用將MySQL對外的端口封閉，並且停止Apache以及所有的用戶進程的方法實現服務器的準安全狀態。最安全的狀態是到服務器的Console上面操作，並且拔掉網線。
2．修改MySQL的登錄設置：

vi /etc/my.cnf 
#在[mysqld]的段中加上一句：skip-grant-tables 
#例如： 
    [mysqld] 
    datadir=/var/lib/mysql 
    socket=/var/lib/mysql/mysql.sock 
    skip-grant-tables 
#保存並且退出vi。

3．重新啓動mysqld

/etc/init.d/mysqld restart 
    Stopping MySQL: [ OK ] 
    Starting MySQL: [ OK ]

4．登錄並修改MySQL的root密碼

# /usr/bin/mysql 
Welcome to the MySQL monitor. Commands end with ; or \g. 
Your MySQL connection id is 3 to server version: 3.23.56 
Type 'help;' or '\h' for help. Type '\c' to clear the buffer. 
mysql> USE mysql ; 
Reading table information for completion of table and column names 
You can turn off this feature to get a quicker startup with -A 
Database changed 
mysql> UPDATE user SET Password = password ( 'new-password' ) WHERE User = 'root' ; 
Query OK, 0 rows affected (0.00 sec) 
Rows matched: 2 Changed: 0 Warnings: 0 
mysql> flush privileges ; 
Query OK, 0 rows affected (0.01 sec) 
mysql> quit 
Bye

5．將MySQL的登錄設置修改回來

vi /etc/my.cnf 
#將剛纔在[mysqld]的段中加上的skip-grant-tables刪除 
#保存並且退出vi。

6．重新啓動mysqld

/etc/init.d/mysqld restart 
    Stopping MySQL: [ OK ] 
    Starting MySQL: [ OK ]

mysql主從同步故障排錯

問題描述：
基本上用mysq都會配置mysql的主從，一方面用mysql的主從做數據庫的讀寫分離，另一方面mysql本身的單機備份不是很強，一般採用主從架構，在從上進行數據備份。在這過程中或多或少出現一些主從不同步的情況，本文將對數據主從不同步的情況進行簡單的總結，主要從數據庫層面上探討數據庫的主從不一致的情況，並不對主從的本身數據不一致引起的主從不同步進行說明：
問題分析：

確認mysql主從服務器的時間是否同步
網絡的延遲

由於mysql主從複製是基於binlog的一種異步複製，通過網絡傳送binlog文件，理所當然網絡延遲是主從不同步的絕大多數的原因，特別是跨機房的數據同步出現這種機率非常的大，所以做讀寫分離，注意從業務層進行前期設計。

主從兩臺機器的負載不一致

由於mysql主從複製是主上面啓動1個io線程，而從上面啓動1個sql線程和1個io線程，當中任何一臺機器的負載很高，忙不過來，導致其中的任何一個線程出現資源不足，都將出現主從不一致的情況。

max_allowed_packet設置不一致

主上面設置的max_allowed_packet比從大，當一個大的sql語句，能在主上面執行完畢，從上面設置過小，無法執行，導致的主從不一致。

key自增鍵開始的鍵值跟自增步長設置不一致引起的主從不一致。
mysql異常宕機情況下，如果未設置sync_binlog=1或innodb_flush_log_at_trx_commit=1很有可能出現binlog或者relaylog文件出現損壞，導致主從不一致。
mysql本身的bug引起的主從不同步。
版本不一致，特別是高版本是主，低版本爲從的情況下，主上面支持的功能，從上面不支持該功能。

mysql的innodb_buffer_pool_size

參考資料：
https://www.cnblogs.com/wanbin/p/9530833.html

Linux&&mysql基礎使用

Linux&&mysql基礎使用

關於數據庫備份方案

冷備份

實現方法

備份前的數據

進行數據備份

模擬誤刪數據庫

進行數據恢復

熱備份

邏輯備份

實現方法

備份前的數據

進行數據備份

模擬誤刪數據庫

進行數據恢復

一個參考腳本

差量備份

增量備份

一個參考腳本

實現方法

備份前數據

模擬第一次增量備份

模擬第二次增量備份

進行數據恢復

使用二進制日誌恢復數據

關於數據庫容災方案

關於數據庫守護方案

關於數據庫（1T）備份、還原方案

關於數據庫備份

關於性能優化

架構優化

查找技巧優化

配置文件優化

發現問題優化

PHP查詢數據庫慢？

mysql服務器頻繁掛掉（down）&&CPU高

Mysql 高負載排查思路

修改mysql密碼

mysql主從同步故障排錯

mysql的innodb_buffer_pool_size