公司有个哥们不小心删除了数据库，之前也没有备份，幸好mysql已经开启了binlog
1、less /etc/mysql.cnf
log-bin=mysql-bin 如果前面加了#，表示注释了，也就是没开启binlog
binlog_format=mixed
datadir = /usr/local/mysql/var binlog日志文件所在目录，重启一次mysql都会产生一个新的binlog文件
2、通过mysqlbinlog从指定位置提取sql
mysqlbinlog --stop-position="1420697" /usr/local/mysql/var/mysql-bin.000083 > /home/Backup_1.sql
mysqlbinlog --start-position="4382351" /usr/local/mysql/var/mysql-bin.000082 > /home/Backup_2.sql
--stop表示把指定位置前面的都导出sql，--start把指定位置之后的都导出，当然是针对当前的binlog文件，不是针对所有binlog文件
如果报mysqlbinlog命令找不到，可以先找到mysql的bin目录，ps -ef|grep mysql，通过这个命令可以找到下面红色的路劲，即为mysql bin目录，然后在bin目录下执行上的命令，注意前面加./
root 10026 1 0 16:36 pts/3 00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --datadir=/usr/local/mysql/var --pid-file=/usr/local/mysql/var/localhost.localdomain.pid
mysql 10409 10026 0 16:36 pts/3 00:00:15 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/usr/local/mysql/var --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=/var/log/mysql/error.log --pid-file=/usr/local/mysql/var/localhost.localdomain.pid --socket=/tmp/mysql.sock --port=3306
3、直接在服务器上执行导入sql，注意先后顺序，-f参数标识忽略错误继续执行
mysql -u root -p -f < Backup_2.sql
mysql -u root -p -f < Backup_2.sql
4、这样做可能会影响到其他库，因为binlog里面记录了所以库的执行日志，所以最好在之心sql之前备份一下其他库，然后关闭binlog，执行sql，再执行其他库的备份sql，最后再开启binlog，关闭和开启binlog都需要重启数据库service mysql restart
5、通过crontab每天自动备份数据库，下面是脚本
- #!/bin/sh
- # mysql_backup.sh: backup mysql databases and keep newest 5 days backup.
- #
- # db_user is mysql username
- # db_passwd is mysql password
- # db_host is mysql host
- # -----------------------------
- db_user="root"
- db_passwd="zhoz.com"
- db_host="localhost"
- # the directory for story your backup file.
- backup_dir="/home/zhozdbbackup"
- # date format for backup file (dd-mm-yyyy)
- time="$(date +"%d-%m-%Y")"
- # mysql, mysqldump and some other bin's path
- MYSQL="/usr/bin/mysql"
- MYSQLDUMP="/usr/bin/mysqldump"
- MKDIR="/bin/mkdir"
- RM="/bin/rm"
- MV="/bin/mv"
- GZIP="/bin/gzip"
- # check the directory for store backup is writeable
- test ! -w $backup_dir && echo "Error: $backup_dir is un-writeable." && exit 0
- # the directory for story the newest backup
- test ! -d "$backup_dir/backup.0/" && $MKDIR "$backup_dir/backup.0/"
- # get all databases
- all_db="$($MYSQL -u $db_user -h $db_host -p$db_passwd -Bse 'show databases')"
- for db in $all_db
- do
- $MYSQLDUMP -u $db_user -h $db_host -p$db_passwd $db | $GZIP -9 > "$backup_dir/backup.0/$time.$db.gz"
- done
- # delete the oldest backup
- test -d "$backup_dir/backup.5/" && $RM -rf "$backup_dir/backup.5"
- # rotate backup directory
- for int in 4 3 2 1 0
- do
- if(test -d "$backup_dir"/backup."$int")
- then
- next_int=`expr $int + 1`
- $MV "$backup_dir"/backup."$int" "$backup_dir"/backup."$next_int"
- fi
- done
- exit 0;