MySQL scheduled full database backup & rolling deletion of backup data before the specified date

Requirements describe

The implementation is as follows MySQL Backup function :

1、 Yes MySQL Library table schema And data Make a scheduled backup
2、 Scroll to delete a specified date ( Such as 30 God ) All backup data before

The test script

vim /data/backup/scripts/MySQL_Backup.sh

#!/bin/bash

# Desc:
# 1. Implements all MySQL databases backup 
# 2. Implements Rolling delete data 30 days ago

set -x

USERNAME="DB_Backuper"
PASSWORD="DB_Backuper"
DBHOST="localhost"
PORT=3306

MySQL_BACKUP_DBLIST="db_1|db_2|db_3|db_4|db_5"
MySQL_STORAGE_BACKUP_PATH="/data/backup/data"
MySQL_BIN_PATH="/usr/bin"

Y_DIR=`(date "-d 0 day ago" +%Y)`
M_DIR=`(date "-d 0 day ago" +%Y%m)`
D_DIR=`(date "-d 0 day ago" +%Y%m%d%H%M)`

Y_LAST_DIR=$(date +%Y "-d -1 year")
TWO_YEARS="$Y_LAST_DIR|$Y_DIR"

# N days ago's data will be deleted
N=30

echo -e "*****************************************"
echo ">>>>>>>>>>>>>>>>>>>>>>> backup started on" `date +%Y/%m/%d--%k:%M:%S`;

for DB in `echo ${
     MySQL_BACKUP_DBLIST//|/ }`; 
	do

	mkdir -p $MySQL_STORAGE_BACKUP_PATH/$DB/$Y_DIR/$M_DIR/$D_DIR
	DB_BACKUP_PATH=$MySQL_STORAGE_BACKUP_PATH/$DB/$Y_DIR/$M_DIR/$D_DIR

	$MySQL_BIN_PATH/mysqldump --host=$DBHOST --user=$USERNAME --password=$PASSWORD --port=$PORT --opt --triggers --routines --single-transaction --set-gtid-purged=OFF $DB | sed 's/DEFINER=`[^`]+`@`[^`]+`/DEFINER=CURRENT_USER/g' > $DB_BACKUP_PATH/$DB.sql

	# Rolling delete data N days ago
	for YEAR in `echo ${
     TWO_YEARS//|/ }`;do
	    PATH_TOBE_CHECK=$MySQL_STORAGE_BACKUP_PATH/$DB/$YEAR
	    if [ -d $PATH_TOBE_CHECK ];then
	        find $PATH_TOBE_CHECK -type d -mtime +$N | xargs rm -rf
	    fi
	done
done;

echo ">>>>>>>>>>>>>>>>>>>>>>> backup ended on" `date +%Y/%m/%d--%k:%M:%S` 
echo -e "*****************************************"

explain :

1. Text substitution
   for … in The syntax requires that data should be separated by spaces , You need to replace the database list with text
   ${MySQL_BACKUP_DBLIST//|/ }
   Be careful } There's a space in front of it
   You can also use it sed To do text substitution .

2. Judge the folder ( Or document ) Non empty
   If the folder or file is empty , An error will be reported when deleting , You only need to check the existing files ( clip ) Just delete .
   ① Determine whether the folder exists : if [ -d $PATH_TOBE_CHECK ]
   ② Determine that the folder does not exist : if [ ! -d $PATH_TOBE_CHECK ]
   ③ If it is the file type , Only need to "-d" Replace parameter with "-f" Parameters .

3. The data of the previous year cannot be deleted in the cross year period ( Ideas can be optimized )
   Specify near 2 Delete the year of