Summary of import, export, backup and recovery of mongodb

The basic chapter （ Can solve the problem of 80% The problem of ）:

1. MongoDB Overview 、 Application scenarios 、 Download mode 、 Connection mode and development history, etc

2. MongoDB data type 、 Key concepts and shell Commonly used instructions

3. MongoDB Various additions to documents 、 to update 、 Delete operation summary

4. MongoDB Summary of various query operations

5. MongoDB Summarize the various operations of the column

6. MongoDB Summary of index operations in

Advanced :

7. MongoDB Summary of aggregation operations

8. MongoDB Import and export of 、 Backup recovery summary

9. MongoDB Summary of user management

10. MongoDB Copy （ Replica set ） summary

11. MongoDB Slice summary

12. MongoDB meet spark（ Integration ）

13. MongoDB Internal storage principle

Other :

14. python3 operation MongoDB Various cases of

15. MongoDB Command summary

One . Import and export

1.1 Export tool mongoexport

Mongodb Medium mongoexport A tool can turn a collection Export to JSON Format or CSV File format . The exported data items can be specified by parameters , You can also export data according to specified conditions .

mongoexport The specific usage is as follows ：

mongoexport -d dbname -c collectionname -o file --type json/csv -f field

Parameter description ：

-d Database name
-c collection name
-o Output file name
—type Format of output , The default is json
-f Output field , If —type by csv, You need to add -f “ Field name ”

Example ： Export set articles, Field _id,author,dave,score,views

[email protected]:/home/mongodump$ sudo mongoexport -d itcast -c articles -o /home/mongodump/articles.json --type json -f  "_id,author,dave,score,views"
2016-09-15T20:33:50.870+0800    connected to: localhost
2016-09-15T20:33:50.871+0800    exported 7 records

1.2 Data import mongoimport

mongoimport The specific usage is as follows ：

mongoimport -d dbname -c collectionname --file filename --headerline --type json/csv -f field

Parameter description ：

-d Database name
-c collection name
—type Import format , Default json
-f Imported field name
—headerline If the imported format is csv, You can use the title of the first row as the imported field
—file File to import

Example ： Import collection articles_import, Field _id,author,dave,score,views

[email protected]:/home/mongodump$ sudo mongoimport -d itcast -c articles_import --file /home/mongodump/articles.json --type json
2016-09-15T20:41:05.682+0800    connected to: localhost
2016-09-15T20:41:05.706+0800    imported 7 documents

Two . Backup recovery

2.1 Why do you need to back up the database regularly

Data backup is to preserve the integrity of data , Prevent power failure , Virus infection and so on , Lose data . If necessary , It's best to back up frequently , Prevent data loss .

The main reason ： Need to know , It's dangerous to surf the Internet on earth , Even if safety precautions are taken , Unforeseen problems will inevitably occur .

2.2 MongoDB The data backup

stay Mongodb Use in mongodump Command to back up MongoDB data . This command can export all data to the specified directory .

mongodump --help: Optional parameter list

mongodump The syntax of the command script is as follows ：

mongodump -h dbhost -d dbname -o dbdirectory
-h：MongDB Address of the server , for example ：127.0.0.1, Of course, you can also specify the port number ：127.0.0.1:27017
-d： Database instances that need to be backed up , for example ：test
-o： Backup data storage location , for example ：/home/mongodump/, Of course, the directory needs to be established in advance , This directory contains the backup data of the database instance .

Case study ： Create a backup database storage location , Execute export command

[email protected]:~$ sudo rm -rf /home/mongodump/
[email protected]:~$ sudo mkdir -p /home/mongodump/
[email protected]:~$ sudo mongodump -h 192.168.17.129:27017 -d itcast -o /home/mongodump/

After executing the above order , Clients will connect to ip by 192.168.17.129 The port number is 27017 Of MongoDB Service , And back up all data to /home/mongodump/ Directory .

2.3 MongoDB Data recovery

mongodb Use mongorerstore Command to restore the backed up data .

mongorestore --help: Optional parameter list

grammar : mongorestore The syntax of the command script is as follows ：

mongorestore -h dbhost -d dbname --dir dbdirectory
-h：MongoDB Address of the server
-d： Database instances that need to be recovered , for example ：test, Of course, this name can also be different from the backup time , such as test2
—dir： Location of backup data , for example ：/home/mongodump/itcast/
—drop： When you recover , Delete the current data first , Then restore the backup data . That is to say , After recovery , The data added and modified after backup will be deleted , Use with caution ！

Next, let's execute the following command :

mongorestore -h 192.168.17.129:27017 -d itcast_restore --dir /home/mongodump/itcast/