Mongodb操作详解

谁借莪１个温暖的怀抱￠ 2022-06-01 06:54 150阅读 0赞

Mongodb操作详解  
C:\\Users\\Administrator>F:  
  
F:\\>cd Mongodb206  
  
F:\\Mongodb206>cd bin  
  
F:\\Mongodb206\\bin>mongo.exe  
MongoDB shell version: 2.0.6  
connecting to: test  
> show dbs;   //显示所有的数据库，相当于mysql的show databases;  
local   (empty) //只有一个local数据库（无表）  
> use local     //选择local数据库  
switched to db local  
> show tables;   //show tables  
>                //无表显示  
> post = \{"title":"My Blog Post",  
... "content":"Here's my blog post.",  
... "created":new Date()\}    
//post字典变量，是javascript语句，如new Date（）  
//其实shell运行环境支持javascript语言，  
\{  
        "title" : "My Blog Post",  
        "content" : "Here's my blog post.",  
        "created" : ISODate("2012-08-11T11:38:08.698Z")  
\}  
> db.blog.insert(post)       
//把post数据输入local数据库中blog(数据库中  
//不存在就自动建立)集合(即表)中  
> db.blog.find()     //将blog中数据全部找出，相当与select \* from blog;  
\{ "\_id" : ObjectId("502644352d31a25926fc6e85"), "title" : "My Blog Post", "conte  
nt" : "Here's my blog post.", "created" : ISODate("2012-08-11T11:38:08.698Z") \}  
>db.blog.findOne()  //只查找集合(表)中一个文档(行)数据  
\{ "\_id" : ObjectId("502644352d31a25926fc6e85"), "title" : "My Blog Post", "conte  
nt" : "Here's my blog post.", "created" : ISODate("2012-08-11T11:38:08.698Z") \}  
更新 update  
> post.comments=\[\]     //给之前的那个post字典变量添加一个comments键值  
\[ \]  
> db.blog.update(\{title:"My Blog Post"\},post)    
//update()至少接受两个参数，第一个为限制条件，第二个为更改内容  
//执行这个后，原文档（行）添加一个字段comments值为空。  
> db.blog.find()  
\{ "\_id" : ObjectId("502644352d31a25926fc6e85"), "title" : "My Blog Post", "conte  
nt" : "Here's my blog post.", "created" : ISODate("2012-08-11T11:38:08.698Z"), "  
comments" : \[ \] \}  
>  
删除 remove delete  
> db.blog.remove(\{title:"My Blog Post"\})  
//删除title为这个的一文档(行)数据  
  
帮助 help  
> help     //查询mongo的javascript shell的帮助  
        db.help()                    help on db methods  
        db.mycoll.help()             help on collection methods  
        rs.help()                    help on replica set methods  
        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 wit  
h time >= 1ms  
        show logs                    show the accessible logger names  
        show log \[name\]              prints out the last segment of log in memor  
y, '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 f  
urther iterate  
        DBQuery.shellBatchSize = x   set default number of items to display on s  
hell  
        exit                         quit the mongo shell  
  
> db.help()         //查询数据库级帮助  
DB methods:  
        db.addUser(username, password\[, readOnly=false\])  
        db.auth(username, password)  
        db.cloneDatabase(fromhost)  
        db.commandHelp(name) returns the help for the command  
        db.copyDatabase(fromdb, todb, fromhost)  
        db.createCollection(name, \{ size : ..., capped : ..., max : ... \} )  
        db.currentOp() displays the current operation in the db  
        db.dropDatabase()  
        db.eval(func, args) run code server-side  
        db.getCollection(cname) same as db\['cname'\] or db.cname  
        db.getCollectionNames()  
        db.getLastError() - just returns the err msg string  
        db.getLastErrorObj() - return full status object  
        db.getMongo() get the server connection object  
        db.getMongo().setSlaveOk() allow this connection to read from the nonmas  
ter member of a replica pair  
        db.getName()  
        db.getPrevError()  
        db.getProfilingLevel() - deprecated  
        db.getProfilingStatus() - returns if profiling is on and slow threshold  
  
        db.getReplicationInfo()  
        db.getSiblingDB(name) get the db at the same server as this one  
        db.isMaster() check replica primary status  
        db.killOp(opid) kills the current operation in the db  
        db.listCommands() lists all the db commands  
        db.logout()  
        db.printCollectionStats()  
        db.printReplicationInfo()  
        db.printSlaveReplicationInfo()  
        db.printShardingStatus()  
        db.removeUser(username)  
        db.repairDatabase()  
        db.resetError()  
        db.runCommand(cmdObj) run a database command.  if cmdObj is a string, tu  
rns it into \{ cmdObj : 1 \}  
        db.serverStatus()  
        db.setProfilingLevel(level,<slowms>) 0=off 1=slow 2=all  
        db.shutdownServer()  
        db.stats()  
        db.version() current version of the server  
        db.getMongo().setSlaveOk() allow queries on a replication slave server  
        db.fsyncLock() flush data to disk and lock server for backups  
        db.fsyncUnock() unlocks server following a db.fsyncLock()  
  
> db.foo.help()           //查询集合(表)级别的帮助  
DBCollection help  
        db.foo.find().help() - show DBCursor help  
        db.foo.count()  
        db.foo.dataSize()  
        db.foo.distinct( key ) - eg. db.foo.distinct( 'x' )  
        db.foo.drop() drop the collection  
        db.foo.dropIndex(name)  
        db.foo.dropIndexes()  
        db.foo.ensureIndex(keypattern\[,options\]) - options is an object with the  
se possible fields: name, unique, dropDups  
        db.foo.reIndex()  
        db.foo.find(\[query\],\[fields\]) - query is an optional query filter. field  
s is optional set of fields to return.  
                                                      e.g. db.foo.find( \{x:77\} ,  
 \{name:1, x:1\} )  
        db.foo.find(...).count()  
        db.foo.find(...).limit(n)  
        db.foo.find(...).skip(n)  
        db.foo.find(...).sort(...)  
        db.foo.findOne(\[query\])  
        db.foo.findAndModify( \{ update : ... , remove : bool \[, query: \{\}, sort:  
 \{\}, 'new': false\] \} )  
        db.foo.getDB() get DB object associated with collection  
        db.foo.getIndexes()  
        db.foo.group( \{ key : ..., initial: ..., reduce : ...\[, cond: ...\] \} )  
        db.foo.mapReduce( mapFunction , reduceFunction , <optional params> )  
        db.foo.remove(query)  
        db.foo.renameCollection( newName , <dropTarget> ) renames the collection  
.  
        db.foo.runCommand( name , <options> ) runs a db command with the given n  
ame where the first param is the collection name  
        db.foo.save(obj)  
        db.foo.stats()  
        db.foo.storageSize() - includes free space allocated to this collection  
        db.foo.totalIndexSize() - size in bytes of all the indexes  
        db.foo.totalSize() - storage allocated for all data and indexes  
        db.foo.update(query, object\[, upsert\_bool, multi\_bool\])  
        db.foo.validate( <full> ) - SLOW  
        db.foo.getShardVersion() - only for use with sharding  
        db.foo.getShardDistribution() - prints statistics about data distributio  
n in the cluster  
>  
  
//想要了解一个函数，可以不写括号()运行，即可打印出该函数的源代码  
> db.foo.update    
function (query, obj, upsert, multi) \{  
    assert(query, "need a query");  
    assert(obj, "need an object");  
    var firstKey = null;  
    for (var k in obj) \{  
        firstKey = k;  
        break;  
    \}  
    if (firstKey != null && firstKey\[0\] == "$") \{  
        this.\_validateObject(obj);  
    \} else \{  
        this.\_validateForStorage(obj);  
    \}  
    this.\_mongo.update(this.\_fullName, query, obj, upsert ? true : false, multi  
? true : false);  
\}  
  
//当集合（表）和db原有的属性相同时  
//如db.version()为得到版本的函数  
//当你创建集合(表)时，创建了同名的时  
//那运行db.version得到的时version()函数源代码  
//办法是运行db.getCollection('version')  
  
更多待续。。。。。。。