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Mongodb詳解與安裝

發(fā)布時間:2020-07-29 11:59:58 來源:網(wǎng)絡 閱讀:734 作者:zouqingyun 欄目:MongoDB數(shù)據(jù)庫

NOSQL的數(shù)據(jù)存儲模型
鍵值模型:(key-avalue存儲)
優(yōu)點:查找速度快
缺點:數(shù)據(jù)無結(jié)構(gòu),通常只被當作字符串或二進制數(shù)據(jù)
應用場景:內(nèi)容緩存
實例:Redis,Dynamo

列式模型
數(shù)據(jù)模型:數(shù)據(jù)按列存儲,將同一列數(shù)據(jù)存在一起。
優(yōu)點:查找迅速,可擴展性強,易于實現(xiàn)分布式
缺點:功能相對SQL很有限
應用場景:分布式文件系統(tǒng)或分布式存儲
實例:Bigtable(google),Cassandra(facebook),HBase(hadoop),Hypertable

文檔模型
數(shù)據(jù)模型:與鍵值模型類似,value指向結(jié)構(gòu)化數(shù)據(jù)
優(yōu)點:數(shù)據(jù)格式要求不嚴格,無需事先定義結(jié)構(gòu)
缺點:查詢性能不高,缺乏統(tǒng)一查詢語法
應用場景:web應用
實例:MongoDB,CouchDB

圖式模型
數(shù)據(jù)模型:圖結(jié)構(gòu)模型
優(yōu)點:利用圖結(jié)構(gòu)相關(guān)算法提高性能,并滿足特珠場景應用需求
缺點:難以實現(xiàn)分布式,功能有定向性
應用場景:社交網(wǎng)絡,推薦系統(tǒng),關(guān)系圖譜
實例:Neo4j
ww.nosql.database.org

 

mongodb
C/S
 mongod
 mongo-->mongod
 mongo>use testdb(不需要分號;結(jié)尾)
 mongo>db.mycollection.insert()
 
 面向collection的數(shù)據(jù)庫
  數(shù)據(jù)庫:但數(shù)據(jù)庫無須創(chuàng)建
  表:行<-->集合:文檔
  集合無須事先定義;

 

 

安裝與配置

1、 創(chuàng)建 /etc/yum.repos.d/mongodb-org-3.0.repo文件

 

[root@hadoop2 ~]# vim /etc/yum.repos.d/mongodb-org-3.0.repo

[mongodb-org-3.0]
name=MongoDB Repostitory
baseurl=https://repo.mongodb.org/yum/redhat/$releasever/mongodb-org/3.0/x86_64/
gpgcheck=0
enabled=1

 #[mongodb-org-2.6]
#name=MongoDB 2.6 Repository
#baseurl=http://downloads-distro.mongodb.org/repo/redhat/os/x86_64/
#gpgcheck=0
#enabled=1
 

 

2、配置

[root@hadoop2 ~]# yum install -y mongodb-org

[root@hadoop2 ~]# mkdir -p /mongod/data

[root@hadoop2 ~]# chown -R mongod.mongod /mongo

[root@hadoop2 ~]# vim /etc/mongod.conf

# mongod.conf

#where to log
logpath=/var/log/mongodb/mongod.log

logappend=true

# fork and run in background
fork=true

#port=27017

dbpath=/mongo/data/                         ##改一下數(shù)據(jù)存放路徑

# location of pidfile
pidfilepath=/var/run/mongodb/mongod.pid

 

[root@hadoop2 mongo]# service mongod start
Starting mongod:                                           [確定]

 

3、基礎操作

[root@hadoop2 mongo]# mongo
MongoDB shell version: 3.0.4
connecting to: test
Welcome to the MongoDB shell.
For interactive help, type "help".
For more comprehensive documentation, see
 http://docs.mongodb.org/
Questions? Try the support group
 http://groups.google.com/group/mongodb-user
Server has startup warnings:
2015-07-21T14:58:55.518+0800 I CONTROL  [initandlisten]
2015-07-21T14:58:55.518+0800 I CONTROL  [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/enabled is 'always'.
2015-07-21T14:58:55.518+0800 I CONTROL  [initandlisten] **        We suggest setting it to 'never'
2015-07-21T14:58:55.518+0800 I CONTROL  [initandlisten]
2015-07-21T14:58:55.519+0800 I CONTROL  [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/defrag is 'always'.
2015-07-21T14:58:55.519+0800 I CONTROL  [initandlisten] **        We suggest setting it to 'never'
2015-07-21T14:58:55.519+0800 I CONTROL  [initandlisten]
2015-07-21T14:58:55.519+0800 I CONTROL  [initandlisten] ** WARNING: soft rlimits too low. rlimits set to 1024 processes, 64000 files. Number of processes should be at least 32000 : 0.5 times number of files.
2015-07-21T14:58:55.519+0800 I CONTROL  [initandlisten]
> help
 db.help()                    help on db methods
 db.mycoll.help()             help on collection methods
 sh.help()                    sharding helpers
 rs.help()                    replica set helpers
 help admin                   administrative help
 help connect                 connecting to a db help
 help keys                    key shortcuts
 help misc                    misc things to know
 help mr                      mapreduce

 show dbs                     show database names
 show collections             show collections in current database
 show users                   show users in current database
 show profile                 show most recent system.profile entries with time >= 1ms
 show logs                    show the accessible logger names
 show log [name]              prints out the last segment of log in memory, 'global' is default
 use <db_name>                set current database
 db.foo.find()                list objects in collection foo
 db.foo.find( { a : 1 } )     list objects in foo where a == 1
 it                           result of the last line evaluated; use to further iterate
 DBQuery.shellBatchSize = x   set default number of items to display on shell
 exit                         quit the mongo shell
> show co
CountDownLatch         connect(               copyDbpath(
compare(               connectionURLTheSame(  copyFile(
compareOn(             constructor
> show dbs
local  0.078GB
> for(i=1;i<=100;i++) db.testcoll.insert({Name: "User"+i,Age: i,Gender: "M",PreferBook: ["first book","Second book"]})
WriteResult({ "nInserted" : 1 })
> db.testcoll.find()
{ "_id" : ObjectId("55adefd39883f07d0866c3b4"), "Name" : "User1", "Age" : 1, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b5"), "Name" : "User2", "Age" : 2, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b6"), "Name" : "User3", "Age" : 3, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b7"), "Name" : "User4", "Age" : 4, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b8"), "Name" : "User5", "Age" : 5, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b9"), "Name" : "User6", "Age" : 6, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ba"), "Name" : "User7", "Age" : 7, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bb"), "Name" : "User8", "Age" : 8, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bc"), "Name" : "User9", "Age" : 9, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bd"), "Name" : "User10", "Age" : 10, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3be"), "Name" : "User11", "Age" : 11, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bf"), "Name" : "User12", "Age" : 12, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c0"), "Name" : "User13", "Age" : 13, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c1"), "Name" : "User14", "Age" : 14, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c2"), "Name" : "User15", "Age" : 15, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c3"), "Name" : "User16", "Age" : 16, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c4"), "Name" : "User17", "Age" : 17, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c5"), "Name" : "User18", "Age" : 18, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c6"), "Name" : "User19", "Age" : 19, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c7"), "Name" : "User20", "Age" : 20, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
Type "it" for more
> it
{ "_id" : ObjectId("55adefd49883f07d0866c3c8"), "Name" : "User21", "Age" : 21, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c9"), "Name" : "User22", "Age" : 22, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ca"), "Name" : "User23", "Age" : 23, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3cb"), "Name" : "User24", "Age" : 24, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3cc"), "Name" : "User25", "Age" : 25, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3cd"), "Name" : "User26", "Age" : 26, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ce"), "Name" : "User27", "Age" : 27, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3cf"), "Name" : "User28", "Age" : 28, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3d0"), "Name" : "User29", "Age" : 29, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3d1"), "Name" : "User30", "Age" : 30, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3d2"), "Name" : "User31", "Age" : 31, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3d3"), "Name" : "User32", "Age" : 32, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3d4"), "Name" : "User33", "Age" : 33, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3d5"), "Name" : "User34", "Age" : 34, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3d6"), "Name" : "User35", "Age" : 35, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3d7"), "Name" : "User36", "Age" : 36, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3d8"), "Name" : "User37", "Age" : 37, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3d9"), "Name" : "User38", "Age" : 38, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3da"), "Name" : "User39", "Age" : 39, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3db"), "Name" : "User40", "Age" : 40, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
Type "it" for more
> it
{ "_id" : ObjectId("55adefd49883f07d0866c3dc"), "Name" : "User41", "Age" : 41, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3dd"), "Name" : "User42", "Age" : 42, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3de"), "Name" : "User43", "Age" : 43, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3df"), "Name" : "User44", "Age" : 44, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3e0"), "Name" : "User45", "Age" : 45, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3e1"), "Name" : "User46", "Age" : 46, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3e2"), "Name" : "User47", "Age" : 47, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3e3"), "Name" : "User48", "Age" : 48, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3e4"), "Name" : "User49", "Age" : 49, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3e5"), "Name" : "User50", "Age" : 50, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3e6"), "Name" : "User51", "Age" : 51, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3e7"), "Name" : "User52", "Age" : 52, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3e8"), "Name" : "User53", "Age" : 53, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3e9"), "Name" : "User54", "Age" : 54, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ea"), "Name" : "User55", "Age" : 55, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3eb"), "Name" : "User56", "Age" : 56, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ec"), "Name" : "User57", "Age" : 57, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ed"), "Name" : "User58", "Age" : 58, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ee"), "Name" : "User59", "Age" : 59, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ef"), "Name" : "User60", "Age" : 60, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
Type "it" for more
> db.testcoll.find().limit(2)
{ "_id" : ObjectId("55adefd39883f07d0866c3b4"), "Name" : "User1", "Age" : 1, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b5"), "Name" : "User2", "Age" : 2, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
> db.testcoll.remove({Age:10})
WriteResult({ "nRemoved" : 1 })
> db.testcoll.find().limit(15)
{ "_id" : ObjectId("55adefd39883f07d0866c3b4"), "Name" : "User1", "Age" : 1, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b5"), "Name" : "User2", "Age" : 2, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b6"), "Name" : "User3", "Age" : 3, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b7"), "Name" : "User4", "Age" : 4, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b8"), "Name" : "User5", "Age" : 5, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b9"), "Name" : "User6", "Age" : 6, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ba"), "Name" : "User7", "Age" : 7, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bb"), "Name" : "User8", "Age" : 8, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bc"), "Name" : "User9", "Age" : 9, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3be"), "Name" : "User11", "Age" : 11, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bf"), "Name" : "User12", "Age" : 12, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c0"), "Name" : "User13", "Age" : 13, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c1"), "Name" : "User14", "Age" : 14, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c2"), "Name" : "User15", "Age" : 15, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c3"), "Name" : "User16", "Age" : 16, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
> db.testcoll.re
db.testcoll.reIndex(           db.testcoll.renameCollection(
db.testcoll.remove(
> db.testcoll.remove({Name:"User14"})
WriteResult({ "nRemoved" : 1 })
> db.testcoll.find().limit(15)
{ "_id" : ObjectId("55adefd39883f07d0866c3b4"), "Name" : "User1", "Age" : 1, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b5"), "Name" : "User2", "Age" : 2, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b6"), "Name" : "User3", "Age" : 3, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b7"), "Name" : "User4", "Age" : 4, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b8"), "Name" : "User5", "Age" : 5, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b9"), "Name" : "User6", "Age" : 6, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ba"), "Name" : "User7", "Age" : 7, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bb"), "Name" : "User8", "Age" : 8, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bc"), "Name" : "User9", "Age" : 9, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3be"), "Name" : "User11", "Age" : 11, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bf"), "Name" : "User12", "Age" : 12, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c0"), "Name" : "User13", "Age" : 13, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c2"), "Name" : "User15", "Age" : 15, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c3"), "Name" : "User16", "Age" : 16, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c4"), "Name" : "User17", "Age" : 17, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
> db.testcoll.update({Name:"User12"},{$set:{Age: 32}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> db.testcoll.find().limit(15)
{ "_id" : ObjectId("55adefd39883f07d0866c3b4"), "Name" : "User1", "Age" : 1, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b5"), "Name" : "User2", "Age" : 2, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b6"), "Name" : "User3", "Age" : 3, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b7"), "Name" : "User4", "Age" : 4, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b8"), "Name" : "User5", "Age" : 5, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b9"), "Name" : "User6", "Age" : 6, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ba"), "Name" : "User7", "Age" : 7, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bb"), "Name" : "User8", "Age" : 8, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bc"), "Name" : "User9", "Age" : 9, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3be"), "Name" : "User11", "Age" : 11, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bf"), "Name" : "User12", "Age" : 32, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c0"), "Name" : "User13", "Age" : 13, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c2"), "Name" : "User15", "Age" : 15, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c3"), "Name" : "User16", "Age" : 16, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c4"), "Name" : "User17", "Age" : 17, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
> db.testcoll.co
db.testcoll.constructor             db.testcoll.copyTo(
db.testcoll.convertToCapped(        db.testcoll.count(
db.testcoll.convertToSingleObject(
> db.testcoll.count()
98
> db.testcoll.find({Age: {$gte:93}})
{ "_id" : ObjectId("55adefd49883f07d0866c410"), "Name" : "User93", "Age" : 93, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c411"), "Name" : "User94", "Age" : 94, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c412"), "Name" : "User95", "Age" : 95, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c413"), "Name" : "User96", "Age" : 96, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c414"), "Name" : "User97", "Age" : 97, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c415"), "Name" : "User98", "Age" : 98, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c416"), "Name" : "User99", "Age" : 99, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c417"), "Name" : "User100", "Age" : 100, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
>
> db.testcoll.find({Age: {$gte:93}},{Name:1,Age:1})
{ "_id" : ObjectId("55adefd49883f07d0866c410"), "Name" : "User93", "Age" : 93 }
{ "_id" : ObjectId("55adefd49883f07d0866c411"), "Name" : "User94", "Age" : 94 }
{ "_id" : ObjectId("55adefd49883f07d0866c412"), "Name" : "User95", "Age" : 95 }
{ "_id" : ObjectId("55adefd49883f07d0866c413"), "Name" : "User96", "Age" : 96 }
{ "_id" : ObjectId("55adefd49883f07d0866c414"), "Name" : "User97", "Age" : 97 }
{ "_id" : ObjectId("55adefd49883f07d0866c415"), "Name" : "User98", "Age" : 98 }
{ "_id" : ObjectId("55adefd49883f07d0866c416"), "Name" : "User99", "Age" : 99 }
{ "_id" : ObjectId("55adefd49883f07d0866c417"), "Name" : "User100", "Age" : 100 }
> db.testcoll.find({$and: [{Age:{$gt: 61}},{Age: {$lt:80}}]})
{ "_id" : ObjectId("55adefd49883f07d0866c3f1"), "Name" : "User62", "Age" : 62, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3f2"), "Name" : "User63", "Age" : 63, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3f3"), "Name" : "User64", "Age" : 64, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3f4"), "Name" : "User65", "Age" : 65, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3f5"), "Name" : "User66", "Age" : 66, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3f6"), "Name" : "User67", "Age" : 67, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3f7"), "Name" : "User68", "Age" : 68, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3f8"), "Name" : "User69", "Age" : 69, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3f9"), "Name" : "User70", "Age" : 70, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3fa"), "Name" : "User71", "Age" : 71, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3fb"), "Name" : "User72", "Age" : 72, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3fc"), "Name" : "User73", "Age" : 73, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3fd"), "Name" : "User74", "Age" : 74, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3fe"), "Name" : "User75", "Age" : 75, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ff"), "Name" : "User76", "Age" : 76, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c400"), "Name" : "User77", "Age" : 77, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c401"), "Name" : "User78", "Age" : 78, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c402"), "Name" : "User79", "Age" : 79, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
> db.testcoll.insert({Name: "User101",Age: 101,Gender: "F",Address: "Beijing,Chian"})
WriteResult({ "nInserted" : 1 })
> db.testcoll.find({Address: {$exists: true}})
{ "_id" : ObjectId("55adf56044061abfb9ba93f2"), "Name" : "User101", "Age" : 101, "Gender" : "F", "Address" : "Beijing,Chian" }
> db.testcoll.find({Address: {$exists: false}})
{ "_id" : ObjectId("55adefd39883f07d0866c3b4"), "Name" : "User1", "Age" : 1, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b5"), "Name" : "User2", "Age" : 2, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b6"), "Name" : "User3", "Age" : 3, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b7"), "Name" : "User4", "Age" : 4, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b8"), "Name" : "User5", "Age" : 5, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3b9"), "Name" : "User6", "Age" : 6, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3ba"), "Name" : "User7", "Age" : 7, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bb"), "Name" : "User8", "Age" : 8, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bc"), "Name" : "User9", "Age" : 9, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3be"), "Name" : "User11", "Age" : 11, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3bf"), "Name" : "User12", "Age" : 32, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c0"), "Name" : "User13", "Age" : 13, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c2"), "Name" : "User15", "Age" : 15, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c3"), "Name" : "User16", "Age" : 16, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c4"), "Name" : "User17", "Age" : 17, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c5"), "Name" : "User18", "Age" : 18, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c6"), "Name" : "User19", "Age" : 19, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c7"), "Name" : "User20", "Age" : 20, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c8"), "Name" : "User21", "Age" : 21, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c3c9"), "Name" : "User22", "Age" : 22, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
Type "it" for more
> db.testcoll.update({Age: {$gt:80}},{$set: {Gender: "F"}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 0 })
> db.testcoll.find({Age: {$gte: 80}})
{ "_id" : ObjectId("55adf56044061abfb9ba93f2"), "Name" : "User101", "Age" : 101, "Gender" : "F", "Address" : "Beijing,Chian" }
{ "_id" : ObjectId("55adefd49883f07d0866c403"), "Name" : "User80", "Age" : 80, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c404"), "Name" : "User81", "Age" : 81, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c405"), "Name" : "User82", "Age" : 82, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c406"), "Name" : "User83", "Age" : 83, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c407"), "Name" : "User84", "Age" : 84, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c408"), "Name" : "User85", "Age" : 85, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c409"), "Name" : "User86", "Age" : 86, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40a"), "Name" : "User87", "Age" : 87, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40b"), "Name" : "User88", "Age" : 88, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40c"), "Name" : "User89", "Age" : 89, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40d"), "Name" : "User90", "Age" : 90, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40e"), "Name" : "User91", "Age" : 91, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40f"), "Name" : "User92", "Age" : 92, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c410"), "Name" : "User93", "Age" : 93, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c411"), "Name" : "User94", "Age" : 94, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c412"), "Name" : "User95", "Age" : 95, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c413"), "Name" : "User96", "Age" : 96, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c414"), "Name" : "User97", "Age" : 97, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c415"), "Name" : "User98", "Age" : 98, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
Type "it" for more
> db.testcoll.update({Age: {$gt:85}},{$set: {Gender: "F"}},{multi:true})
WriteResult({ "nMatched" : 16, "nUpserted" : 0, "nModified" : 15 })
> db.testcoll.find({Age: {$gte: 80}})
{ "_id" : ObjectId("55adf56044061abfb9ba93f2"), "Name" : "User101", "Age" : 101, "Gender" : "F", "Address" : "Beijing,Chian" }
{ "_id" : ObjectId("55adefd49883f07d0866c403"), "Name" : "User80", "Age" : 80, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c404"), "Name" : "User81", "Age" : 81, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c405"), "Name" : "User82", "Age" : 82, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c406"), "Name" : "User83", "Age" : 83, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c407"), "Name" : "User84", "Age" : 84, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c408"), "Name" : "User85", "Age" : 85, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c409"), "Name" : "User86", "Age" : 86, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40a"), "Name" : "User87", "Age" : 87, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40b"), "Name" : "User88", "Age" : 88, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40c"), "Name" : "User89", "Age" : 89, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40d"), "Name" : "User90", "Age" : 90, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40e"), "Name" : "User91", "Age" : 91, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40f"), "Name" : "User92", "Age" : 92, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c410"), "Name" : "User93", "Age" : 93, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c411"), "Name" : "User94", "Age" : 94, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c412"), "Name" : "User95", "Age" : 95, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c413"), "Name" : "User96", "Age" : 96, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c414"), "Name" : "User97", "Age" : 97, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c415"), "Name" : "User98", "Age" : 98, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
Type "it" for more
> db.testcoll.update({Name: "User92"},{$unset:{PreferBooks: ""}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 0 })
> db.testcoll.find({Age: {$gte: 80}})
{ "_id" : ObjectId("55adf56044061abfb9ba93f2"), "Name" : "User101", "Age" : 101, "Gender" : "F", "Address" : "Beijing,Chian" }
{ "_id" : ObjectId("55adefd49883f07d0866c403"), "Name" : "User80", "Age" : 80, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c404"), "Name" : "User81", "Age" : 81, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c405"), "Name" : "User82", "Age" : 82, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c406"), "Name" : "User83", "Age" : 83, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c407"), "Name" : "User84", "Age" : 84, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c408"), "Name" : "User85", "Age" : 85, "Gender" : "M", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c409"), "Name" : "User86", "Age" : 86, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40a"), "Name" : "User87", "Age" : 87, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40b"), "Name" : "User88", "Age" : 88, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40c"), "Name" : "User89", "Age" : 89, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40d"), "Name" : "User90", "Age" : 90, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40e"), "Name" : "User91", "Age" : 91, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c40f"), "Name" : "User92", "Age" : 92, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c410"), "Name" : "User93", "Age" : 93, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c411"), "Name" : "User94", "Age" : 94, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c412"), "Name" : "User95", "Age" : 95, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c413"), "Name" : "User96", "Age" : 96, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c414"), "Name" : "User97", "Age" : 97, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
{ "_id" : ObjectId("55adefd49883f07d0866c415"), "Name" : "User98", "Age" : 98, "Gender" : "F", "PreferBook" : [ "first book", "Second book" ] }
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