MongoDB creates a database

MongoDB creates a database

Grammar

MongoDB creates the database in the following syntax format:

use DATABASE_NAME

If the database does not exist, create the database or switch to the specified database.

Instance

Here's an example of us creating a database youj:

> use youj
switched to db youj
> db
youj
> 

If you want to see all the databases, you can use the show dbs command:

> show dbs
local  0.078GB
test   0.078GB
> 

As you can see, the database we just created, youj, is not in the list of databases, and to display it, we need to insert some data into the youj database.

> db.youj.insert({"name":"W3Cschool教程"})
WriteResult({ "nInserted" : 1 })
> show dbs
local   0.078GB
youj  0.078GB
test    0.078GB
> 

The default database in MongoDB is test, and if you don't create a new database, the collection will be stored in the test database.