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How to use driver in mongodb? In view of this problem, this article introduces the corresponding analysis and answers in detail, hoping to help more partners who want to solve this problem to find a more simple and feasible way.

MongoDB is a database based on distributed file storage. Written in C++ language. Designed to provide scalable high-performance data storage solutions for WEB applications.

MongoDB is a product between relational database and non-relational database, which is the most functional and most like relational database in non-relational database.

1 Environmental preparation

Create the project and add the following dependencies:

Org.mongodb mongodb-driver 3.10.1

2 using mongodb-driver

2.1 query all

@ Test public void test1 () {/ / create connection MongoClient client = new MongoClient ("192.168.200.128"); / / Open database MongoDatabase commentdb = client.getDatabase ("commentdb"); / / get collection MongoCollection comment = commentdb.getCollection ("comment"); / / query FindIterable documents = comment.find () / / query records to get the document collection for (Document document: documents) {System.out.println ("_ id:" + document.get ("_ id")); System.out.println ("content:" + document.get ("content")); System.out.println ("user ID:" + document.get ("userid")); System.out.println ("likes:" + document.get ("thumbup")) } / / close the connection client.close ();}}

2.2 query based on _ id

MongoCollection is used for each use to extract:

Private MongoClient client; private MongoCollection comment; @ Before public void init () {/ / create a connection client = new MongoClient ("192.168.200.128"); / / Open the database MongoDatabase commentdb = client.getDatabase ("commentdb"); / / get the collection comment = commentdb.getCollection ("comment");} @ After public void after () {client.close () } @ Test public void test2 () {/ / query FindIterable documents = comment.find (new BasicDBObject ("_ id", "1")); / / query records to get a collection of documents for (Document document: documents) {System.out.println ("_ id:" + document.get ("_ id")); System.out.println ("content:" + document.get ("content")) System.out.println ("user ID:" + document.get ("userid")); System.out.println ("likes:" + document.get ("thumbup"));}}

2.3 New

@ Test public void test3 () {Map map = new HashMap (); map.put ("_ id", "6"); map.put ("content", "great!") ; map.put ("userid", "9999"); map.put ("thumbup", 123); Document document = new Document (map); comment.insertOne (document);}

2.4 Modification

@ Test public void test4 () {/ / modified condition Bson filter = new BasicDBObject ("_ id", "6"); / / modified data Bson update = new BasicDBObject ("$set", new Document ("userid", "8888")); comment.updateOne (filter, update);}

2.5 Delete

@ Test public void test5 () {/ / deleted condition Bson filter = new BasicDBObject ("_ id", "6"); comment.deleteOne (filter);}

Advantages and disadvantages of MongoDB

Advantages:

1. The performance of MongoDB in an appropriate amount of memory is very fast. It stores hot data in physical memory, which makes the reading and writing of hot data very fast.

2. The high availability of MongoDB and the high scalability of cluster architecture.

3. In the replica set, when the master database encounters problems and cannot continue to provide services, the replica set will elect a new master library to continue to provide services.

4. The data in Bson and JSon format of MongoDB are very suitable for storage and query in document format.

Disadvantages:

1. Transaction operations are not supported. MongoDB does not have its own transaction mechanism. If you need to implement the transaction mechanism in MongoDB, you need to logically implement the transaction by yourself through an additional table.

2. There is less application experience, because the rise time of NoSQL is short, the application experience is less than that of relational database.

3. MongoDB takes up too much space.

This is the answer to the question about how to use driver in mongodb. I hope the above content can be of some help to you. If you still have a lot of doubts to solve, you can follow the industry information channel for more related knowledge.

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