一个简单的MySQL备份Shell脚本

#!/bin/bash
#this is a script of mysql backup 
if [ ! -d /mydata/data1/backup ] ;then 
 mkdir /mydata/data1/backup
fi
cd /mydata/data1/backup
file=$(find . -type f -mtime -7 | grep .*all.sql)  #查找7天内是否有备份的文件
echo $file
if [ -z $file ] ;then 
 echo "backup all databases..."
 backupfile=$(date +%F-%H-%M-%S)
 mysqldump -uroot --lock-all-tables --flush-logs --master-data=2 --all-databases > /mydata/data1/backup/"$backupfile-all.sql"
 if [ $ -eq 0 ] ;then
 echo "Accomplish,file is $backupfile-all.sql !"
 else 
 echo " Failure !!! "
 fi
else                   #查找倒数第二大的二进制文件，作增量备份
 cd ..
 echo "All database backups ,now start doing incremental backups!"
    a=1 
    b=1 
    for file in $(ls |grep mysql-bin |grep -v index);do
        num=$(echo $file |cut -d. -f2 )
        if [ $num -gt $a ];then
            a=$num
        fi 
    done
    unset num file
    num=1  
    for file in $(ls |grep mysql-bin |grep -v index);do
        num=$(echo $file |cut -d. -f2 )
        if [ $num -gt $b -a $num -ne $a ] ; then
            b=$num
            tmp=$file
        fi 
    done
    file1=$(echo $tmp|cut -d. -f1)
    file2=$(echo $tmp|cut -d. -f2)
    mysqlbinlog $tmp > /mydata/data1/backup/"$file1-$file2.sql"
 if [ $ -eq 0 ] ;then 
 echo "Backup completed,file is "$file1-$file2.sql""
 fi
fi