数据库应用：MongoDB 数据备份与恢复

目录

一、实验

1.MongoDB 数据库备份与恢复

2.MongoDB 数据表备份与恢复

二、问题

1.MongoDB有哪些命令行工具实现数据备份与恢复

---

一、实验

1.MongoDB 数据库备份与恢复

（1）查看版本

root@node1:~# mongo --version

（2）准备测试数据，mongoDB终端下进行以下操作，插入200000条数据

use demo
fotmatnumber = (start, end)=>{
    num = Math.round(Math.random() * (end-start)) + start
    if(num<10){
        return "0"+num;
    }else{
        return num;
    }
}

rand_title = (i)=>{
    num = Math.round( Math.random() * 10 );
    num1 = Math.round( Math.random() * 10 );
    return [
        "赠送礼品-"+num,
        "购物狂欢-"+num,
        "随便买买-"+num,
        "愉快购物-"+num,
        "赠送礼物-"+num,
        "商品购买-"+num,
        "买多送多-"+num,
        "买年货-"+num,
        "买买买买-"+num,
        "充值会员-"+num
    ][num1];
}

for(var i=0; i<200000; i++){  
    db.orders.insert({
        "onumber": ( "0000000000000000" + i ).substr( String(i).length ),  
        "date": "20"+fotmatnumber(0,21)+"-"+fotmatnumber(1,12)+"-"+fotmatnumber(1,31),  
        "title": rand_title(i),
        "user_id": parseInt(i/200)+1,
        "items" :[{ 
        	"goods_id" : parseInt(i/200)+1,
        	"goods_attr" : i,  
        	"price" : 100.0
        },{ 
        	"goods_id" : parseInt(i/200)+2,
        	"goods_attr" : i+1,  
        	"price" : 80.0
        }]
    })
    if(i%10000==0){
        print("已经添加了"+parseInt(i/10000)+"万条数据！");
    }
}

（2）查看demo数据库大小

root@node1:~# mongo
……
> show dbs;
admin   0.000GB
config  0.000GB
demo    0.010GB
local   0.000GB
> exit
bye

(3) 数据备份

root@node1:~# mongodump -h 127.0.0.1:27017 -d demo -o backup

（4）删除demo数据库

root@node1:~# mongo
……
> show dbs;
admin   0.000GB
config  0.000GB
demo    0.010GB
local   0.000GB
> use demo;
switched to db demo
> db.dropDatabase()
{ "dropped" : "demo", "ok" : 1 }
> show dbs;
admin   0.000GB
config  0.000GB
local   0.000GB
> exit
bye

（5）数据恢复

root@node1:~# mongorestore -h 127.0.0.1:27017 -d demo --dir /root/backup/demo

（6）查看数据恢复情况

root@node1:~# mongo
……
> use dbs;
switched to db dbs
> show dbs;
admin   0.000GB
config  0.000GB
demo    0.009GB
local   0.000GB

2.MongoDB 数据表备份与恢复

（1）查询demo数据表的orders数据表文件（默认每次20个）

……
> use demo;
switched to db demo
> show tables;
orders
> db.orders.find()

（2）输入it遍历查询后20个文件

Type "it" for more
> it

（3）修改返回结果数据的单页显示数量为30条，默认20条

> DBQuery.shellBatchSize=30
30

（4）删除orders表中的多个文档 ，目前显示剩余190078条文档

> db.orders.deleteMany({"title":"买买买买-1"})
{ "acknowledged" : true, "deletedCount" : 2037 }
> db.orders.deleteMany({"title":"买买买买-3"})
{ "acknowledged" : true, "deletedCount" : 1988 }
> db.orders.deleteMany({"title":"买买买买-4"})
{ "acknowledged" : true, "deletedCount" : 2062 }
> db.orders.deleteMany({"title":"买买买买-5"})
{ "acknowledged" : true, "deletedCount" : 1902 }
> db.orders.deleteMany({"title":"买买买买-8"})
{ "acknowledged" : true, "deletedCount" : 1933 }
> db.order.count()
0
> db.orders.count()
190078
> exit
bye

（5）数据进行恢复

--drop 恢复数据前，先删除MongoDB中的旧数据

root@node1:~# mongorestore -h 127.0.0.1:27017 -d demo --dir /root/backup/demo --drop
2023-11-26T21:21:23.636-0800	The --db and --collection flags are deprecated for this use-case; please use --nsInclude instead, i.e. with --nsInclude=${DATABASE}.${COLLECTION}
2023-11-26T21:21:23.637-0800	building a list of collections to restore from /root/backup/demo dir
2023-11-26T21:21:23.637-0800	reading metadata for demo.orders from /root/backup/demo/orders.metadata.json
2023-11-26T21:21:23.638-0800	dropping collection demo.orders before restoring
2023-11-26T21:21:23.667-0800	restoring demo.orders from /root/backup/demo/orders.bson
2023-11-26T21:21:25.993-0800	finished restoring demo.orders (200000 documents, 0 failures)
2023-11-26T21:21:25.993-0800	no indexes to restore for collection demo.orders
2023-11-26T21:21:25.993-0800	200000 document(s) restored successfully. 0 document(s) failed to restore.

（6）查看恢复情况

root@node1:~# mongo
……
> use demo;
switched to db demo
> db.orders.count()
200000
> exit
bye

（7）数据导出

root@node1:~# mongoexport -d demo -c orders -o /root/backup/orders.json --type json
2023-11-26T21:24:52.113-0800	connected to: mongodb://localhost/
2023-11-26T21:24:53.117-0800	[##......................]  demo.orders  24000/200000  (12.0%)
2023-11-26T21:24:54.117-0800	[######..................]  demo.orders  56000/200000  (28.0%)
2023-11-26T21:24:55.116-0800	[########................]  demo.orders  72000/200000  (36.0%)
2023-11-26T21:24:56.116-0800	[############............]  demo.orders  104000/200000  (52.0%)
2023-11-26T21:24:57.117-0800	[################........]  demo.orders  136000/200000  (68.0%)
2023-11-26T21:24:58.117-0800	[####################....]  demo.orders  168000/200000  (84.0%)
2023-11-26T21:24:59.056-0800	[########################]  demo.orders  200000/200000  (100.0%)
2023-11-26T21:24:59.056-0800	exported 200000 records

（8）查看导出文件，一共200000条

（9）删除数据表orders

root@node1:~/backup# mongo
……
> use demo;
switched to db demo
> show tables;
orders
> db.orders.drop()
true
> show tables;
> exit
bye

（10）导入数据进行恢复

root@node1:~/backup# mongoimport -d demo -c orders --file /root/backup/orders.json --type json
2023-11-26T21:29:06.494-0800	connected to: mongodb://localhost/
2023-11-26T21:29:09.495-0800	[########................] demo.orders	16.7MB/48.0MB (34.8%)
2023-11-26T21:29:12.495-0800	[################........] demo.orders	32.0MB/48.0MB (66.8%)
2023-11-26T21:29:15.311-0800	[########################] demo.orders	48.0MB/48.0MB (100.0%)
2023-11-26T21:29:15.311-0800	200000 document(s) imported successfully. 0 document(s) failed to import.

（11）查看恢复情况

root@node1:~/backup# mongo
……
> use demo
switched to db demo
> show tables;
orders
> db.orders.count()
200000
> exit
bye

二、问题

1.MongoDB有哪些命令行工具实现数据备份与恢复

（1）命令行工具

MongdoDB一共提供了4个命令行工具给我们对数据进行备份与恢复以及导入与导出数据。

（2）备份与恢复

备份与恢复操作的数据文件格式是bson格式，二进制

1）数据备份
mongodump -h dbhost -d dbname -o dbdirectory
# 例如：备份一个demo的数据库
mongodump -h 127.0.0.1:27017 -d demo -o /root/backup

2)数据恢复
mongorestore -h dbhost -d dbname --dir dbdirectory --drop
# 例如：恢复上面备份的demo数据库
mongorestore -h 127.0.0.1:27017 -d demo --dir /root/backup/demo

(3) 导入与导出

导入与导出数据的数据文件格式是json格式，文本格式

1） 数据导出
mongoexport -d dbname -c collectionname -o file --type json/csv -f field
# 例如：导出demo数据库的orders集合数据
mongoexport -d demo -c orders -o /root/backup/orders.json --type json

2) 数据导入
mongoimport -d dbname -c collectionname --file filename --headerline --type json/csv -f field
# 例如：把上面导出的json中的数据，导入到demo数据库的orders集合中
mongoimport -d demo -c orders --file /order/backup/orders.json --type json