MongoDb 命令查询所有数据库列表

 MongoDb 命令查询所有数据库列表CODE:> show dbs如果想查看当前连接在哪个数据库下面，可以直接输入dbCODE:> dbAdmin想切换到test数据库下面CODE:> use testswitched to db test> dbTest想查看test下有哪些表或者叫collection，可以输入CODE:> show collectionssystem.indexesuser想知道mongodb支持哪些命令，可以直接输入helpCODE:> helpDos代码  收藏代码    HELP            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            use <db name>                set curent database to <db name>            db.help()                    help on DB methods            db.foo.help()                help on collection methods            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  如果想知道当前数据库支持哪些方法：CODE:> db.help();Java代码  收藏代码    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 a replica 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 database command.  if cmdObj is a string, turns it into { cmdObj : 1 }            db.setProfilingLevel(level) 0=off 1=slow 2=all            db.shutdownServer()            db.version() current version of the server  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：CODE:> db.user.help();  user为表名Java代码  收藏代码    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-----------------------通过条件查询： 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 with collection  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 , <optional params> )      db.foo.remove(query) 根据条件删除数据      db.foo.renameCollection( newName ) renames the collection  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 shardingMongodb的备份工具mongodump如果想备份数据库test 如：CODE:[[e-mail]  ~/mongodb/bin]$ ./mongodump --helpoptions:--help                   produce help message-h [ --host ] arg        mongo host to connect to-d [ --db ] arg          database to use-c [ --collection ] arg  collection to use (some commands)-u [ --username ] arg    username-p [ --password ] arg    password--dbpath arg             directly access mongod data files in this path,                         instead of connecting to a mongod instance-v [ --verbose ]         be more verbose (include multiple times for more                         verbosity e.g. -vvvvv)-o [ --out ] arg (=dump) output directory[[e-mail]  ~/mongodb/bin]$ ./mongodump -d test -o test/connected to: 127.0.0.1DATABASE: test         to         test/test      test.user to test/test/user.bson               100000 objects      test.system.indexes to test/test/system.indexes.bson               1 objects[[e-mail]  ~/mongodb/bin]$ ls2     mongo   mongodump    mongofiles   mongorestore  mongosniffdump  mongod  mongoexport  mongoimport  mongos     testMongoDB的数据恢复工具mongorestore查看test库中的表CODE:> show collectionssystem.indexesUser删除user表CODE:> db.user.drop();True> show collectionsSystem.indexes现在利用mongorestore表恢复刚才利用mongodump备份的数据CODE:[[e-mail]  ~/mongodb/bin]$ ./mongorestore --helpusage: ./mongorestore [options] [directory or filename to restore from]options:--help                  produce help message-h [ --host ] arg       mongo host to connect to-d [ --db ] arg         database to use-c [ --collection ] arg collection to use (some commands)-u [ --username ] arg   username-p [ --password ] arg   password--dbpath arg            directly access mongod data files in this path,                        instead of connecting to a mongod instance-v [ --verbose ]        be more verbose (include multiple times for more                        verbosity e.g. -vvvvv)[[e-mail]  ~/mongodb/bin]$ ./mongorestore -d test -c user test/test/user.bsonconnected to: 127.0.0.1test/test/user.bson       going into namespace [test.user]       100000 objectsUser表中的10w条记录已经恢复CODE:> show collectionssystem.indexesuser> 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   1. 超级用户相关：         #增加或修改用户密码         db.addUser('admin','pwd')         #查看用户列表         db.system.users.find()         #用户认证         db.auth('admin','pwd')         #删除用户         db.removeUser('mongodb')         #查看所有用户         show users         #查看所有数据库         show dbs         #查看所有的collection         show collections         #查看各collection的状态         db.printCollectionStats()         #查看主从复制状态         db.printReplicationInfo()         #修复数据库         db.repairDatabase()         #设置记录profiling，0=off 1=slow 2=all         db.setProfilingLevel(1)         #查看profiling         show profile         #拷贝数据库         db.copyDatabase('mail_addr','mail_addr_tmp')         #删除collection         db.mail_addr.drop()         #删除当前的数据库         db.dropDatabase()   2. 客户端连接          /usr/local/mongodb/bin/mongo user_addr -u user -p 'pwd'   3. 增删改           #存储嵌套的对象          db.foo.save({'name':'ysz','address':{'city':'beijing','post':100096},'phone':[138,139]})          #存储数组对象          db.user_addr.save({'Uid':'[e-mail]','Al':['[e-mail]','[e-mail]']})          #根据query条件修改，如果不存在则插入，允许修改多条记录          db.foo.update({'yy':5},{'$set':{'xx':2}},upsert=true,multi=true)          #删除yy=5的记录          db.foo.remove({'yy':5})          #删除所有的记录         db.foo.remove()   4. 索引          增加索引：1(ascending),-1(descending)          db.things.ensureIndex({firstname: 1, lastname: 1}, {unique: true});          #索引子对象          db.user_addr.ensureIndex({'Al.Em': 1})          #查看索引信息          db.deliver_status.getIndexes()          db.deliver_status.getIndexKeys()          #根据索引名删除索引          db.user_addr.dropIndex('Al.Em_1')   5. 查询          查找所有          db.foo.find()          #查找一条记录          db.foo.findOne()          #根据条件检索10条记录          db.foo.find({'msg':'Hello 1'}).limit(10)          #sort排序          db.deliver_status.find({'From':'[e-mail]'}).sort({'Dt',-1})          db.deliver_status.find().sort({'Ct':-1}).limit(1)         #count操作         db.user_addr.count()         #distinct操作         db.foo.distinct('msg')         #>操作         db.foo.find({"timestamp": {"$gte" : 2}})         #子对象的查找         db.foo.find({'address.city':'beijing'})   6. 管理          查看collection数据的大小          db.deliver_status.dataSize()          #查看colleciont状态          db.deliver_status.stats()          #查询所有索引的大小          db.deliver_status.totalIndexSize()