shell脚本定时备份MySQL数据库数据并保留指定时间

#!/bin/sh

# 数据库账号信息
DB_USER="root"
DB_PWD="root"
DB_HOST="127.0.0.1"
DB_PORT="3306"

# MYSQL所在目录
MYSQL_DIR="/home/mysql"
# 备份文件存放目录
BAK_DIR="/home/db_backup"
# 时间格式化，如 20200902
DATE=`date +%Y%m%d`
# 备份脚本保存的天数
DEL_DAY=7

# 要备份的数据库，空格分隔
DATABASES=("apolloconfigdb" "apolloportaldb" "apolloconfigdb-uat" "frame-assistor" "frame-authorization" )

# 创建日期目录
mkdir $BAK_DIR/$DATE

echo "-------------------$(date +%F_%T) start ---------------" >>${BAK_DIR}/db_backup.log
for database in "${DATABASES[@]}"
do
  # 执行备份命令
  $MYSQL_DIR/bin/mysqldump --opt -u$DB_USER -p$DB_PWD -h$DB_HOST -P$DB_PORT ${database} > $BAK_DIR/$DATE/${database}.sql
done

echo "--- backup file created: $BAK_DIR/db_backup_$DATE.tar.gz" >>${BAK_DIR}/db_backup.log

# 将备份好的sql脚本压缩到db_backup_yyyyMMdd.tar.gz
tar -czf $BAK_DIR/db_backup_$DATE.tar.gz $BAK_DIR/$DATE

# 压缩后，删除压缩前的备份文件和目录
rm -f $BAK_DIR/$DATE/*
rmdir $BAK_DIR/$DATE

# 遍历备份目录下的压缩文件
LIST=$(ls ${BAK_DIR}/db_backup_*)
# 获取截止时间，早于该时间的文件将删除
SECONDS=$(date -d "$(date +%F) -${DEL_DAY} days" +%s)

for index in ${LIST}
do
  # 对文件名进行格式化，取命名末尾的时间，格式如 20200902
  timeString=$(echo ${index} | egrep -o "?[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]")
  if [ -n "$timeString" ]
  then
    indexDate=${timeString//./-}
    indexSecond=$( date -d ${indexDate} +%s )
    # 与当天的时间做对比，把早于7天的备份文件删除
    if [ $(( $SECONDS- $indexSecond )) -gt 0 ]
    then
      rm -f $index
      echo "---- deleted old backup file : $index " >>${BAK_DIR}/db_backup.log
    fi
  fi
done

echo "-------------------$(date +%F_%T) end ---------------" >>${BAK_DIR}/db_backup.log

# 每天凌晨3点执行
0 3 * * * sh /home/backupDB.sh > /dev/null 2>&1 &