mongo DB的一般操作

最近接触了一些mongoDB 。将一些指令操作记录下来，便于查询和使用

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[root@logs ~]# mongo -u loguser -p log123456 --authenticationDatabase admin
MongoDB shell version: 2.4.10
connecting to: test
> show users
> post = {"title":"My Blog Post","Content":"Here is my blog Post.","Date":new Date()}
{
"title" : "My Blog Post",
"Content" : "Here is my blog Post.",
"Date" : ISODate("2015-02-11T03:12:03.061Z")
}

插入
--插入文档对象
> db.blog.insert(post)
> post = {"title":"Licz Blog Post","Content":"Here is my blog Post.","Date":new Date()}
{
"title" : "Licz Blog Post",
"Content" : "Here is my blog Post.",
"Date" : ISODate("2015-02-11T03:17:07.219Z")
}
> db.blog.insert(post)

读取
--读取集合里一个文档
> db.blog.findOne()
{
"_id" : ObjectId("54dac88dc956bbcbefa8151c"),
"title" : "My Blog Post",
"Content" : "Here is my blog Post.",
"Date" : ISODate("2015-02-11T03:12:03.061Z")
}

--读取限定文档数
> db.blog.find().limit(100);
> db.blog.find().limit(100);
{ "_id" : ObjectId("54dac88dc956bbcbefa8151c"), "title" : "My Blog
Post", "Content" : "Here is my blog Post.", "Date" :
ISODate("2015-02-11T03:12:03.061Z") }
{ "_id" : ObjectId("54dac9b8c956bbcbefa8151d"), "title" : "Licz Blog
Post", "Content" : "Here is my blog Post.", "Date" :
ISODate("2015-02-11T03:17:07.219Z") }

--读取所有文档数
> db.blog.find()
{ "_id" : ObjectId("54dac88dc956bbcbefa8151c"), "title" : "My Blog
Post", "Content" : "Here is my blog Post.", "Date" :
ISODate("2015-02-11T03:12:03.061Z") }
> db.blog.find().limit(100);
{ "_id" : ObjectId("54dac88dc956bbcbefa8151c"), "title" : "My Blog
Post", "Content" : "Here is my blog Post.", "Date" :
ISODate("2015-02-11T03:12:03.061Z") }
{ "_id" : ObjectId("54dac9b8c956bbcbefa8151d"), "title" : "Licz Blog
Post", "Content" : "Here is my blog Post.", "Date" :
ISODate("2015-02-11T03:17:07.219Z") }

更新

--修改变量post,增加comments键
> post
{ "title" : "You Blog Post", "Date" : ISODate("2015-02-11T03:18:10.509Z") }
> post.comments=[]
[ ]
> db.blog.update({title:"You Blog Post"},post)
> db.blog.find()
{ "_id" : ObjectId("54dac88dc956bbcbefa8151c"), "title" : "My Blog
Post", "Content" : "Here is my blog Post.", "Date" :
ISODate("2015-02-11T03:12:03.061Z") }
{ "_id" : ObjectId("54dac9b8c956bbcbefa8151d"), "title" : "Licz Blog
Post", "Content" : "Here is my blog Post.", "Date" :
ISODate("2015-02-11T03:17:07.219Z") }
{ "_id" : ObjectId("54dac9f8c956bbcbefa8151e"), "title" : "You Blog
Post", "Date" : ISODate("2015-02-11T03:18:10.509Z"), "comments" : [ ] }

删除

--删除title限定条件的文档
> db.blog.remove({title:"You Blog Post"})
> db.blog.find()
{ "_id" : ObjectId("54dac88dc956bbcbefa8151c"), "title" : "My Blog
Post", "Content" : "Here is my blog Post.", "Date" :
ISODate("2015-02-11T03:12:03.061Z") }
{ "_id" : ObjectId("54dac9b8c956bbcbefa8151d"), "title" : "Licz Blog
Post", "Content" : "Here is my blog Post.", "Date" :
ISODate("2015-02-11T03:17:07.219Z") }
>

MongoDB使用技巧

--help帮助命令
> 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

--特殊集合名处理
如果集合名恰好是和数据库类的一个属性名相同，可以使用db.getCollection进行访问

> db.version
function (){
return this.serverBuildInfo().version;
}
> db.getCollection("version")
test.version