``` #!/bin/sh # 數據庫認證 user="***" password="*******" host="localhost" db_name="****" port="3306" # 備份路徑 bak_path=/data/sql_bak/$db_name #保存備份個數 number=3 if [ -d $bak_path ];then echo $bak_path exsits else echo "mkdir $bak_path" mkdir -p $bak_path fi # Dump數據庫到SQL文件 mysqldump -u$user -p$password -h $host -x $db_name > $bak_path/$(date -I).sql #寫創建備份日志 echo "create $bak_path/$(date -I).sql" >> $bak_path/log.txt #找出需要刪除的備份 delfile=`ls -l -crt $bak_path/*.sql | awk '{print $9 }' | head -1` #判斷現在的備份數量是否大于$number count=`ls -l -crt $bak_path/*.sql | awk '{print $9 }' | wc -l` if [ $count -gt $number ];then rm $delfile #寫刪除文件日志 echo "delete $delfile" >> $bak_path/log.txt fi ```