#!/bin/bash# 保存备份个，备份31天的数据number=31# 备份保存路径backup_dir=/home/mysql/data/mysqlbackup# 日期dd=`data+%Y-%m-%d-%H-%M-%S`# 备份工具tool=mysqldump# 用户名username=name# 密码，特殊字符要转化password=pwd# 要备份的数据库database_name=数据库名# 如果文件夹不存在则创建if [.! -d $backup_dir ];then    mkdir -p $backup_dir;fi$tool -u $username -p$password $database_name >$backup_dir/$dataabase_name-$dd.sql# 写创建备份日志echo "create $backup_dir/$database_name-$dd.dupm" >>$backup_dir/log.txt# 找出需要删除的备份delfile=`ls -l -crt $backup_dir/*.sql | awk '{print $9}' |head -l`# 判断现在的备份数量是否大雨$numbercount=`ls -l -crt $backup_dir/*sql | awk '{print}' | wc -l`if [.$count -gt $number ]then    # 删除最早生成的备份，只保留number数量的备份    rm $delfile    # 写删除文件日志    echo "delete $delfile" >> $backup_dir/log.txtfi

crontab -e0 5 * * * /root/bin/backup.sh

mysqldump -u 'user' -p 'password' database1 > database1.sql

mysqldump -u 'user' -p 'password' database1 database2 > database1_ database2.sql

mysqldump -u 'user' -p 'password' database1 table1 > database1_table1.sql

mysqldump -u 'user' -p 'password' database1 table1 table2 > database1_table1_table2.sql

mysqldump -h'127.0.0.1' -u 'user' -p 'password' database1 > database1.sql