转自：https://www.cnblogs.com/leffss/p/7832047.html

#!/bin/bash
#全备方式，一般在从机上执行，适用于小中型mysql数据库
#删除15天以前备份
#作者：fafu_li
#时间：2015.08.10

source /etc/profile        #加载系统环境变量
source ~/.bash_profile    #加载用户环境变量
set -o nounset             #引用未初始化变量时退出
#set -o errexit            #执行shell命令遇到错误时退出

user="root"
password="123456"
host="localhost"
port="3306"
#需备份的数据库，数组
db=("test")
#备份时加锁方式，
#MyISAM为锁表--lock-all-tables，
#InnoDB为锁行--single-transaction
lock="--single-transaction"
mysql_path="/usr/local/mysql"
backup_path="${mysql_path}/backup"
date=$(date +%Y-%m-%d_%H-%M-%S)
day=15
backup_log="${mysql_path}/backup.log"

#建立备份目录
if [ ! -e $backup_path ];then
    mkdir -p $backup_path
fi

#删除以前备份
find $backup_path -type f -mtime +$day -exec rm -rf {} \; > /dev/null 2>&1

echo "开始备份数据库：${db[*]}"

#备份并压缩
backup_sql(){
    dbname=$1
    backup_name="${dbname}_${date}.sql"
    #-R备份存储过程，函数，触发器
    mysqldump -h $host -P $port -u $user -p$password $lock --default-character-set=utf8 --flush-logs -R $dbname > $backup_path/$backup_name    
    if [[ $? == 0 ]];then
        cd $backup_path
        tar zcpvf $backup_name.tar.gz $backup_name
        size=$(du $backup_name.tar.gz -sh | awk \'{print $1}\')
        rm -rf $backup_name
        echo "$date 备份 $dbname($size) 成功 "
    else
        cd $backup_path
        rm -rf $backup_name
        echo "$date 备份 $dbname 失败 "
    fi
}

#循环备份
length=${#db[@]}
for (( i = 0; i < $length; i++ )); do
        backup_sql ${db[$i]} >> $backup_log 2>&1
done

echo "备份结束,结果查看 $backup_log"
du $backup_path/*$date* -sh | awk \'{print "文件:" $2 ",大小:" $1}\'