Basic syntax of mongodb

1. Start shell: (the terminal should select linux when mainly using crt software, otherwise the Backspace key can sometimes go wrong.)

[root@saltstack mongodb] # mongo

> show dbs # View the database

Admin (empty)

Local 0.078GB

Modbtest 0.078GB

Myinfo (empty)

Test (empty)

Xiaoluo 0.078GB

> use dbtest # uses a database. If not, it will be created automatically.

Switched to db dbtest

# create a dictionary document, which is stored in key,value:

> test = {'id':1,'name':'xiaoming','job':'it'}

{"id": 1, "name": "xiaoming", "job": "it"}

> test

{"id": 1, "name": "xiaoming", "job": "it"}

# automatically create a table called dbtest, and then insert the dictionary test into it:

> db.dbtest.insert (test)

WriteResult ({"nInserted": 1})

# or you can insert data manually:

> db.dbtest.insert ({'id':2,'name':'xiaoli','job':'it'})

WriteResult ({"nInserted": 1})

# how to use find to view data:

> db.dbtest.find ()

{"_ id": ObjectId ("5513375e83aef55e0cc2d05c"), "id": 1, "name": "xiaoming", "job": "it"}

{"_ id": ObjectId ("5513379383aef55e0cc2d05d"), "id": 2, "name": "xiaoli", "job": "it"}

> show tables

Dbtest

System.indexes

# find according to the condition

> db.dbtest.find ({'id':1})

{"_ id": ObjectId ("5513375e83aef55e0cc2d05c"), "id": 1, "name": "xiaoming", "job": "it"}

# update the selection according to the conditions

> db.dbtest.update ({'id':2}, {' id':2,'name':'xiaoluo','job':'it'})

WriteResult ({"nMatched": 1, "nUpserted": 0, "nModified": 1})

> db.dbtest.find ({'id':2})

{"_ id": ObjectId ("5513379383aef55e0cc2d05d"), "id": 2, "name": "xiaoluo", "job": "it"}

>

# use the remove method to delete according to conditions. Delete id=2 's dictionary:

> db.dbtest.remove ({'id':2})

WriteResult ({"nRemoved": 1})

> db.dbtest.find ()

{"_ id": ObjectId ("5513375e83aef55e0cc2d05c"), "id": 1, "name": "xiaoming", "job": "it"}