MongoDB Learning Notes-database operations

Use Use the database name to create the database and return the database statement formatIf it already exists: usedatabase_name

>use mynewdb

Switched to DB mynewdb

Use ? db name to check the currently used database

> DB

Mynewdb

using Commands ? show dbs? to check the list of databases.

> Show DBS

Gnymongo 0.078GB

Gnyworkflowdemo 0.078GB

Loginfo 0.078GB

......

the database you just created mynewdb? does not appear in the list. In order for the database to appear, at least one document should be inserted

Db.test.insert ({"X": 1})

If you want to delete a new database ? mynewdb, use this as follows ? Dropdatabase ()? Method

>use mynewdb

Switched to DB mynewdb

> Db.dropdatabase ()

relational database and MongoDB The comparison of the database in some terms

show dbs

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relational database (MySQL)	MongoDB	remarks
create database mynewdb	use mynewdb	CREATE database
use mynewdb	use mynewdb	Toggle and use database
select database ()	db	Check the currently used database
show databases	Check database list
Drop Database mynewdb	Db.dropdatabase ()	Check Database list

MongoDB Learning Notes-database operations