MongoDB的shell命令

深藏阁楼爱情的钟 2022-08-06 07:19 167阅读 0赞

如果想查看当前连接在哪个数据库下面，可以直接输入db

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`>db Admin`想切换到test数据库下面

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`>use test switched to db test > db Test`想查看test下有哪些表或者叫collection，可以输入

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`>show collections system.indexes user`想知道mongodb支持哪些命令，可以直接输入help

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`>help HELP      showdbs              show database names      showcollections         show collections in currentdatabase      showusers             show users in current database      showprofile            showmost recent system.profile entries with time >=1ms      use<db name>           set curent database to <dbname>      db.help()              helpon DB methods      db.foo.help()           help on collection methods      db.foo.find()           list objects in collection foo      db.foo.find({ a : 1 } )    listobjects in foo where a == 1      it                  result of the last line evaluated; use tofurther iterate`如果想知道当前数据库支持哪些方法：

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`>db.help(); DB methods:      db.addUser(username,password) 添加数据库授权用户      db.auth(username,password)           访问认证      db.cloneDatabase(fromhost)克隆数据库      db.commandHelp(name)returns the help for the command      db.copyDatabase(fromdb,todb,fromhost)  复制数据库      db.createCollection(name,{ size : ..., capped : ..., max : ... } ) 创建表      db.currentOp()displays the current operation in the db      db.dropDatabase()      删除当前数据库      db.eval_r(func,args) run code server-side      db.getCollection(cname)same as db['cname'] or db.cname      db.getCollectionNames()      获取当前数据库的表名      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 nonmaster member of areplica pair      db.getName()      db.getPrevError()      db.getProfilingLevel()      db.getReplicationInfo()      db.getSisterDB(name)get the db at the same server as this onew      db.killOp()kills the current operation in the db      db.printCollectionStats()  打印各表的状态信息      db.printReplicationInfo()      打印主数据库的复制状态信息      db.printSlaveReplicationInfo()      打印从数据库的复制状态信息      db.printShardingStatus()           打印分片状态信息      db.removeUser(username)删除数据库用户      db.repairDatabase()修复数据库      db.resetError()      db.runCommand(cmdObj)run a databasecommand.  if cmdObjis a string, turns it into { cmdObj : 1 }      db.setProfilingLevel(level)0=off 1=slow 2=all      db.shutdownServer()      db.version()current version of theserver`如果想知道当前数据库下的表或者表collection支持哪些方法，可以使用一下命令如：

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`>db.user.help();  user为表名 DBCollection help      db.foo.count()           统计表的行数      db.foo.dataSize()      统计表数据的大小      db.foo.distinct(key ) - eg. db.foo.distinct( 'x' )           按照给定的条件除重      db.foo.drop()drop the collection 删除表      db.foo.dropIndex(name)  删除指定索引      db.foo.dropIndexes()删除所有索引      db.foo.ensureIndex(keypattern,options)- options should be an object with these possible fields: name,unique,dropDups  增加索引      db.foo.find([query] , [fields]) - first parameter is an optional query filter.second parameter is optional set of fields to return.根据条件查找数据                             e.g. db.foo.find( { x : 77 } , { name : 1, x : 1 } )      db.foo.find(...).count()      db.foo.find(...).limit(n)根据条件查找数据并返回指定记录数      db.foo.find(...).skip(n)      db.foo.find(...).sort(...)查找排序      db.foo.findOne([query])根据条件查询只查询一条数据      db.foo.getDB()get DB object associated withcollection  返回表所属的库      db.foo.getIndexes()显示表的所有索引      db.foo.group({ key : ..., initial: ..., reduce : ...[, cond: ...] } )根据条件分组      db.foo.mapReduce(mapFunction , reduceFunction , <optionalparams> )      db.foo.remove(query)根据条件删除数据      db.foo.renameCollection(newName ) renames thecollection  重命名表      db.foo.save(obj)保存数据      db.foo.stats()  查看表的状态      db.foo.storageSize()- includes free space allocated to this collection 查询分配到表空间大小      db.foo.totalIndexSize()- size in bytes of all the indexes 查询所有索引的大小      db.foo.totalSize()- storage allocated for all data and indexes 查询表的总大小      db.foo.update(query,object[, upsert_bool]) 根据条件更新数据      db.foo.validate()- SLOW 验证表的详细信息      db.foo.getShardVersion()- only for use with sharding`Mongodb的备份工具mongodump  
  
如果想备份数据库test 如：

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`[falcon@www.fwphp.cn  ~/mongodb/bin]$./mongodump --help options:  --help             produce help message  -h [ --host ]arg      mongohost to connect to  -d [ --db ]arg       database to use  -c [ --collection ]arg  collection touse (some commands)  -u [ --username ]arg   username  -p [ --password ]arg   password  --dbpatharg         directly access mongod data files in thispath,                  instead of connecting to a mongodinstance  -v [ --verbose]      be more verbose (include multiple timesfor more                  verbosity e.g. -vvvvv)  -o [ --out ] arg (=dump) outputdirectory [falcon@www.fwphp.cn  ~/mongodb/bin]$[color=Blue]./mongodump -d test -o test/[/color] connected to: 127.0.0.1 DATABASE: test      to      test/test      test.userto test/test/user.bson            100000objects      test.system.indexesto test/test/system.indexes.bson            1objects [falcon@www.fwphp.cn  ~/mongodb/bin]$ls 2    mongo  mongodump   mongofiles  mongorestore  mongosniff dump  mongod  mongoexport  mongoimport  mongos    test`MongoDB的数据恢复工具mongorestore  
  
查看test库中的表

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`>show collections system.indexes User`删除user表

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`>db.user.drop(); True > show collections System.indexes`现在利用mongorestore表恢复刚才利用mongodump备份的数据

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`[falcon@www.fwphp.cn  ~/mongodb/bin]$./mongorestore --help usage: ./mongorestore [options] [directory or filename to restorefrom] options:  --help            produce help message  -h [ --host ]arg     mongo host to connect to  -d [ --db ]arg      database to use  -c [ --collection ] arg collectionto use (some commands)  -u [ --username ]arg  username  -p [ --password ]arg  password  --dbpatharg        directly access mongod data files in thispath,                  insteadof connecting to a mongod instance  -v [ --verbose]      bemore verbose (include multiple times for more                  verbositye.g. -vvvvv) [falcon@www.fwphp.cn  ~/mongodb/bin]$./mongorestore -d test -c user test/test/user.bson connected to: 127.0.0.1 test/test/user.bson      going into namespace [test.user]      100000 objects`User表中的10w条记录已经恢复

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`>show collections system.indexes user > db.user.find(); { "_id" : ObjectId("4b9c8db08ead0e3347000000"), "uid" : 1,"username" : "Falcon.C-1" } { "_id" : ObjectId("4b9c8db08ead0e3347010000"), "uid" : 2,"username" : "Falcon.C-2" } { "_id" : ObjectId("4b9c8db08ead0e3347020000"), "uid" : 3,"username" : "Falcon.C-3" } { "_id" : ObjectId("4b9c8db08ead0e3347030000"), "uid" : 4,"username" : "Falcon.C-4" } { "_id" : ObjectId("4b9c8db08ead0e3347040000"), "uid" : 5,"username" : "Falcon.C-5" } ................. has more`mongodb还提供了HTTP查看运行状态及restfull的接口  
默认的访问端口是28017