NOSQL的數(shù)據(jù)存儲模型
鍵值模型:(key-avalue存儲)
優(yōu)點(diǎn):查找速度快
缺點(diǎn):數(shù)據(jù)無結(jié)構(gòu),通常只被當(dāng)作字符串或二進(jìn)制數(shù)據(jù)
應(yīng)用場景:內(nèi)容緩存
實(shí)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(diǎn):查找迅速,可擴(kuò)展性強(qiáng),易于實(shí)現(xiàn)分布式
缺點(diǎn):功能相對SQL很有限
應(yīng)用場景:分布式文件系統(tǒng)或分布式存儲
實(shí)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(diǎn):數(shù)據(jù)格式要求不嚴(yán)格,無需事先定義結(jié)構(gòu)
缺點(diǎn):查詢性能不高,缺乏統(tǒng)一查詢語法
應(yīng)用場景:web應(yīng)用
實(shí)例:MongoDB,CouchDB
圖式模型
數(shù)據(jù)模型:圖結(jié)構(gòu)模型
優(yōu)點(diǎn):利用圖結(jié)構(gòu)相關(guān)算法提高性能,并滿足特珠場景應(yīng)用需求
缺點(diǎn):難以實(shí)現(xiàn)分布式,功能有定向性
應(yīng)用場景:社交網(wǎng)絡(luò),推薦系統(tǒng),關(guān)系圖譜
實(shí)例:Neo4j
ww.nosql.database.org
目前成都創(chuàng)新互聯(lián)已為1000多家的企業(yè)提供了網(wǎng)站建設(shè)、域名、網(wǎng)站空間、網(wǎng)站運(yùn)營、企業(yè)網(wǎng)站設(shè)計(jì)、葉縣網(wǎng)站維護(hù)等服務(wù),公司將堅(jiān)持客戶導(dǎo)向、應(yīng)用為本的策略,正道將秉承"和諧、參與、激情"的文化,與客戶和合作伙伴齊心協(xié)力一起成長,共同發(fā)展。
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(chǔ)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.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" ] }
Type "it" for more