mongodb与sql语句对照表

inert into users value(3,5)	db.users.insert({a:3,b:5})
select a,b from users	db.users.find({}, {a:1,b:1})
select * from users	db.users.find()
select * from users where age=33	db.users.find({age:33})
select a,b from users where age=33	db.users.find({age:33}, {a:1,b:1})
select * from users where age=33 order by name	db.users.find({age:33}).sort({name:1})
select * from users where age>33	db.users.find({age:{$gt:33}})
select * from users where age!=33	db.users.find({age:{$ne:33}})
select * from users where name like "%Joe%"	db.users.find({name:/Joe/})
select * from users where name LIKE "Joe%"	db.users.find({name:/^Joe/})
select * from users where age>33 and age<=40	db.users.find({'age':{$gt:33,$lte:40}})
select * from users order by name desc	db.users.find().sort({name:-1})
select * from users where a=1 and b='q'	db.users.find({a:1,b:'q'})
select * from users limit 10 skip 20	db.users.find().limit(10).skip(20)
select * from users where a=1 or b=2	db.users.find( { $or : [ { a : 1 } , { b : 2 } ] } )
select * from users limit 1	db.users.findOne()
select order_id from orders o, order_line_items li where li.order_id=o.order_id and li.sku=12345	db.orders.find({"items.sku":12345},{_id:1})
select customer.name from customers,orders where orders.id="q179" and orders.custid=customer.id	var o = db.orders.findOne({_id:"q179"}); var name = db.customers.findOne({_id:o.custid})
select distinct last_name from users	db.users.distinct('last_name')
select count(*y) from users	db.users.count()
select count(*y) from users where age > 30	db.users.find({age: {'$gt': 30}}).count()
select count(age) from users	db.users.find({age: {'$exists': true}}).count()
create index myindexname on users(name)	db.users.ensureIndex({name:1})
create index myindexname ON users(name,ts desc)	db.users.ensureIndex({name:1,ts:-1})
explain select * from users where z=3	db.users.find({z:3}).explain()
update users set a=1 where b='q'	db.users.update({b:'q'}, {$set:{a:1}}, false, true)
update users set a=a+2 where b='q'	db.users.update({b:'q'}, {$inc:{a:2}}, false, true)
delete from users where z="abc"	db.users.remove({z:'abc'});

更多命令

db.AddUser(username,password)  添加用户

db.auth(usrename,password)     设置数据库连接验证

db.cloneDataBase(fromhost)     从目标服务器克隆一个数据库
db.commandHelp(name)           returns the help for the command
db.copyDatabase(fromdb,todb,fromhost)  复制数据库fromdb---源数据库名称，todb---目标数据库名称，fromhost---源数据库服务器地址
db.createCollection(name,{size:3333,capped:333,max:88888})  创建一个数据集，相当于一个表
db.currentOp()                 取消当前库的当前操作
db.dropDataBase()              删除当前数据库
db.eval(func,args)             run code server-side
db.getCollection(cname)        取得一个数据集合，同用法：db['cname'] or
db.getCollenctionNames()       取得所有数据集合的名称列表
db.getLastError()              返回最后一个错误的提示消息
db.getLastErrorObj()           返回最后一个错误的对象
db.getMongo()                  取得当前服务器的连接对象get the server
db.getMondo().setSlaveOk()     allow this connection to read from then nonmaster membr of a replica pair
db.getName()                   返回当操作数据库的名称
db.getPrevError()              返回上一个错误对象
db.getProfilingLevel()         
db.getReplicationInfo()        获得重复的数据
db.getSisterDB(name)           get the db at the same server as this onew
db.killOp()                    停止（杀死）在当前库的当前操作
db.printCollectionStats()      返回当前库的数据集状态
db.printReplicationInfo()
db.printSlaveReplicationInfo()
db.printShardingStatus()       返回当前数据库是否为共享数据库
db.removeUser(username)        删除用户
db.repairDatabase()            修复当前数据库
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()            关闭当前服务程序
db.version()                   返回当前程序的版本信息

db.test.find({id:10})          返回test数据集ID=10的数据集
db.test.find({id:10}).count()  返回test数据集ID=10的数据总数
db.test.find({id:10}).limit(2) 返回test数据集ID=10的数据集从第二条开始的数据集
db.test.find({id:10}).skip(8)  返回test数据集ID=10的数据集从0到第八条的数据集
db.test.find({id:10}).limit(2).skip(8)  返回test数据集ID=1=的数据集从第二条到第八条的数据
db.test.find({id:10}).sort()   返回test数据集ID=10的排序数据集
db.test.findOne([query])       返回符合条件的一条数据
db.test.getDB()                返回此数据集所属的数据库名称
db.test.getIndexes()           返回些数据集的索引信息
db.test.group({key:...,initial:...,reduce:...[,cond:...]})
db.test.mapReduce(mayFunction,reduceFunction,<optional params>)
db.test.remove(query)                      在数据集中删除一条数据
db.test.renameCollection(newName)          重命名些数据集名称
db.test.save(obj)                          往数据集中插入一条数据
db.test.stats()                            返回此数据集的状态
db.test.storageSize()                      返回此数据集的存储大小
db.test.totalIndexSize()                   返回此数据集的索引文件大小
db.test.totalSize()                        返回些数据集的总大小
db.test.update(query,object[,upsert_bool]) 在此数据集中更新一条数据
db.test.validate()                         验证此数据集
db.test.getShardVersion()                  返回数据集共享版本号

MongoDB语法与现有关系型数据库SQL语法比较

MongoDB语法                                   MySql语法
db.test.find({'name':'foobar'}) <==> select * from test where name='foobar'
db.test.find()                  <==> select * from test
db.test.find({'ID':10}).count() <==> select count(*) from test where ID=10
db.test.find().skip(10).limit(20)     <==> select * from test limit 10,20
db.test.find({'ID':{$in:[25,35,45]}}) <==> select * from test where ID in (25,35,45)
db.test.find().sort({'ID':-1})        <==> select * from test order by ID desc
db.test.distinct('name',{'ID':{$lt:20}})  <==> select distinct(name) from test where ID<20
db.test.group({key:{'name':true},cond:{'name':'foo'},reduce:function(obj,prev){prev.msum+=obj.marks;},initial:{msum:0}})  <==> select name,sum(marks) from test group by name
db.test.find('this.ID<20',{name:1})  <==> select name from test where ID<20
db.test.insert({'name':'foobar','age':25})<==>insert into test ('name','age') values('foobar',25)
db.test.remove({})                <==> delete * from test
db.test.remove({'age':20})        <==> delete test where age=20
db.test.remove({'age':{$lt:20}})  <==> elete test where age<20
db.test.remove({'age':{$lte:20}}) <==> delete test where age<=20
db.test.remove({'age':{$gt:20}})  <==> delete test where age>20
db.test.remove({'age':{$gte:20}}) <==> delete test where age>=20
db.test.remove({'age':{$ne:20}})  <==> delete test where age!=20
db.test.update({'name':'foobar'},{$set:{'age':36}}) <==> update test set age=36 where name='foobar'
db.test.update({'name':'foobar'},{$inc:{'age':3}})  <==> update test set age=age+3 where name='foobar'

注意以上命令大小写敏感