Mongodb数据库命令端常用操作
数据库基本命令操作 数据库常用命令 1、Help查看命令提示 help db.help(); db.yourColl.help(); db.youColl.find().help(); rs.help(); 2、切换/创建数据库 use yourDB; 当创建一个集合(table)的时候会自动创建当前数据库 3、查询所有数据库 show dbs; 4、删
数据库基本命令操作
数据库常用命令
1、Help查看命令提示
help
db.help();
db.yourColl.help();
db.youColl.find().help();
rs.help();
2、切换/创建数据库
use yourDB; 当创建一个集合(table)的时候会自动创建当前数据库
3、查询所有数据库
show dbs;
4、删除当前使用数据库
db.dropDatabase();
5、从指定主机上克隆数据库
db.cloneDatabase(“127.0.0.1”); 将指定机器上的数据库的数据克隆到当前数据库
6、从指定的机器上复制指定数据库数据到某个数据库
db.copyDatabase("mydb", "temp", "127.0.0.1");将本机的mydb的数据复制到temp数据库中
7、修复当前数据库
db.repairDatabase();
8、查看当前使用的数据库
db.getName();
db; db和getName方法是一样的效果,都可以查询当前使用的数据库
9、显示当前db状态
db.stats();
10、当前db版本
db.version();
11、查看当前db的链接机器地址
db.getMongo();
Collection聚集集合
1、创建一个聚集集合(table)
db.createCollection(“collName”, {size: 20, capped: 5, max: 100});
2、得到指定名称的聚集集合(table)
db.getCollection("account");
3、得到当前db的所有聚集集合
db.getCollectionNames();
4、显示当前db所有聚集索引的状态
db.printCollectionStats();
用户相关
1、添加一个用户
db.addUser("name");
db.addUser("userName", "pwd123", true); 添加用户、设置密码、是否只读
2、数据库认证、安全模式
db.auth("userName", "123123");
3、显示当前所有用户
show users;
4、删除用户
db.removeUser("userName");
错误信息操作
1、查询之前的错误信息 db.getPrevError(); 2、清除错误记录 db.resetError();
查看聚集集合基本信息
1、查看帮助 db.yourColl.help(); 2、查询当前集合的数据条数 db.yourColl.count(); 3、查看数据空间大小 db.userInfo.dataSize(); 4、得到当前聚集集合所在的db db.userInfo.getDB(); 5、得到当前聚集的状态 db.userInfo.stats(); 6、得到聚集集合总大小 db.userInfo.totalSize(); 7、聚集集合储存空间大小 db.userInfo.storageSize(); 8、Shard版本信息 db.userInfo.getShardVersion() 9、聚集集合重命名 db.userInfo.renameCollection("users"); 将userInfo重命名为users 10、删除当前聚集集合 db.userInfo.drop();
索引操作
1、创建索引 db.userInfo.ensureIndex({name: 1}); db.userInfo.ensureIndex({name: 1, ts: -1}); 2、查询当前聚集集合所有索引 db.userInfo.getIndexes(); 3、查看总索引记录大小 db.userInfo.totalIndexSize(); 4、读取当前集合的所有index信息 db.users.reIndex(); 5、删除指定索引 db.users.dropIndex("name_1"); 6、删除所有索引索引 db.users.dropIndexes();
查询操作
Mongodb-SpringMvc下Query数据库操作SQL
http://blog.csdn.net/xiaohulunb/article/details/27828381
1.查询所有
> db.foo.find() { "_id" : ObjectId("5389aa1df06b88aaa313746a"), "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } } { "_id" : ObjectId("5389aaa4afce65313a5614f7"), "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "_id" : ObjectId("5389aabaafce65313a5614f8"), "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 186 ] } } { "_id" : ObjectId("5389aac5afce65313a5614f9"), "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } }
2.显示指定列
第一个{} 放where条件 第二个{} 指定哪些列显示和不显示 (0表示不显示 >0表示显示)
后面演示使用{'_id':0} 默认隐藏‘_id列’减少显示量
> db.foo.find({},{'_id':0,'name':1,'user':1}) { "name" : "yiwa", "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "user" : { "phone" : [ 63, 137 ] } }
3.使用and操作
#名字是yiwa且年龄是25岁
> db.foo.find({'name':'yiwa','age':25},{'_id':0}) { "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } }
4.使用or操作
#名字是yiwa或者年龄是75岁
> db.foo.find({'$or':[{'name':'yiwa'},{'age':75}]},{'_id':0}) { "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } }
5.使用<, <=, >, >= ($lt, $lte, $gt, $gte )操作,取模运算$mod
#年龄在 15<= x <=75 岁
> db.foo.find({'age':{'$gte':15,'$lte':75}},{'_id':0}) { "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } }
# 对age%3==1的取模结果
> db.foo.find({'age':{'$mod':[3,1]}},{'_id':0}) { "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 186 ] } }
6.使用in, not in ($in, $nin)
#名字不是siwa且年龄在[15,25,85]
> db.foo.find({'name':{'$nin':['siwa']},'age':{'$in':[15,25,85]}},{'_id':0}) { "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 186 ] } }
7.匹配null操作
#名字是null的
> db.foo.find({'name':null},{'_id':0}) >
8.使用like (mongoDB 支持正则表达式)
#名字like%iwa%的 #名字like yi%的
> db.foo.find({'name':/iwa/},{'_id':0}) { "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } > db.foo.find({'name':/^yi/},{'_id':0}) { "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } }
9.使用distinct、count查询
> db.foo.distinct('name') [ "yiwa", "erwa", "sanwa", "siwa" ] > db.foo.count() 4
#distinct结合条件,排序使用
> db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 95, "user" : { "phone" : [ 123, 133, 186 ] } } { "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 133, 137, 186 ] } } > db.foo.distinct("age",{'user.phone':{'$in':[63,65,186]}}).sort({'age':1}) [ 25, 85, 95 ] > db.foo.distinct("age",{'user.phone':{'$in':[63,65,186]}}).sort({'age':-1}) [ 25, 85, 95 ] > db.foo.distinct("age",{'user.phone':{'$in':[63,65,186]}}) [ 25, 95, 85 ]
待解疑问:?为什么 排序时候 age :-1 与 age :1 结果一样?
10.数组查询 (mongoDB自己特有的)(all,size)
#电话中含有186的
> db.foo.find({'user.phone':186},{'_id':0}) { "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 186 ] } }
#电话中含有188,186的
> db.foo.find({'user.phone':{'$all':[188,186]}},{'_id':0}) { "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } }
#电话中有2个值的
> db.foo.find({'user.phone':{'$size':2}},{'_id':0}) { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } }
11.exists判断是否存在,type判断类型,Sort排序
#name中值是字符型,age中值是整型,按name升序,age降序
> db.foo.find({'name':{'$type':2},'age':{'$type':16}},{'_id':0}).sort({'name':1,'age':-1}) { "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } }
#name中值存在的:true #name中值不存在的:false
> db.foo.find({'name':{'$exists':true}},{'_id':0}) { "name" : "yiwa", "age" : 25, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } > db.foo.find({'name':{'$exists':false}},{'_id':0}) >
12.$elemMatch数组元素匹配
#插入测试数据
> db.foo.save({x:[{'a':1,'b':5},999,'liw',{'a':12},{'b':100}]}) WriteResult({ "nInserted" : 1 })
#查询某元素中a=1,b=5的元素
> db.foo.find({'x':{'$elemMatch':{'a':1,b:{'$gt':4}}}},{'_id':0}) { "x" : [ { "a" : 1, "b" : 5 }, 999, "liw", { "a" : 12 }, { "b" : 100 } ] } > db.foo.find({'x.a':1,'x.b':5},{'_id':0}) { "x" : [ { "a" : 1, "b" : 5 }, 999, "liw", { "a" : 12 }, { "b" : 100 } ] }
更新操作
1.update( criteria, objNew, upsert, multi)、save() 方法
criteria : update的查询条件,类似sql update查询内where后面的
objNew : update的对象和一些更新的操作符(如$,$inc...)等,也可以理解为sql update查询内set后面的
upsert : 这个参数的意思是,如果不存在update的记录,是否插入objNew,true为插入,默认是false,不插入。
multi : mongodb默认是false,只更新找到的第一条记录,如果这个参数为true,就把按条件查出来多条记录全部更新。
save()方法相当于upsert与multi 都为true时候
> db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 55, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } > db.foo.update({'age':{$gte:30}},{$set:{'age':55}},fasle,false) 2014-05-31T19:36:05.407+0800 ReferenceError: fasle is not defined > db.foo.update({'age':{$gte:30}},{$set:{'age':55}},false,false) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 0 }) > db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 55, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } > db.foo.update({'age':{$gte:30}},{$set:{'age':56}},false,false) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 56, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } > db.foo.update({'age':{$gte:300}},{$set:{'age':56}},true,false) WriteResult({ "nMatched" : 0, "nUpserted" : 1, "nModified" : 0, "_id" : ObjectId("5389bee8afce65313a5614fa") }) > db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 56, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 75, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 85, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } { "age" : 56 } > db.foo.update({'age':{$gte:30}},{$set:{'age':56}},true,true) WriteResult({ "nMatched" : 4, "nUpserted" : 0, "nModified" : 2 }) > db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 56, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 56, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 56, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } { "age" : 56 }
2.$inc 对于数字字段的值增加value
#年龄大于30的 全部age值增加20
> db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 58, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 56, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 56, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } > db.foo.update({'age':{$gte:30}},{$inc:{'age':20}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 78, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 56, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 56, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } }
3.$set 相当于sql的set field = value
#年龄=56的,设置为名字='laoda',年龄=65
> db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 78, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "erwa", "age" : 56, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 56, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } > db.foo.update({'age':56},{$set:{'name':'laoda','age':65}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 78, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "laoda", "age" : 65, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 56, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } }
#只更新了一条数据,因为 multi 默认为false
4.$unset 删除字段
#查询name='laoda',user字段存在的数据中,删除age=65的age字段
> db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 78, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "laoda", "age" : 65, "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 56, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } { "age" : 65, "name" : "laoda" } > db.foo.update({'name':'laoda','user':{$exists:true}},{$unset:{"age":65}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.foo.find({},{'_id':0}) { "name" : "yiwa", "age" : 78, "user" : { "phone" : [ 123, 13, 186 ] } } { "name" : "laoda", "user" : { "phone" : [ 63, 188, 13, 186 ] } } { "name" : "sanwa", "age" : 56, "user" : { "phone" : [ 186 ] } } { "name" : "siwa", "age" : 15, "user" : { "phone" : [ 63, 137 ] } } { "age" : 65, "name" : "laoda" }
5.$push 数组下操作
#把value追加到field里面去,field一定要是数组类型才行,如果field不存在,会新增一个数组类型加进去
> db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda" } > db.array.update({'name':'laoda','age':65},{$push:{"phone":65}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 65 ] } > db.array.update({'name':'laoda','age':65},{$push:{"phone":[65,75,{'iphone':'188'},85]}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 65, [ 65, 75, { "iphone" : "188" }, 85 ] ] }
6.$pushAll 数组下操作
#一次可以追加多个值到数组
> db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda" } > db.array.update({'name':'laoda','age':65},{$pushAll:{"phone":[111,222]}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111, 222 ] } > db.array.update({'name':'laoda','age':65},{$pushAll:{"phone":[111,222]}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111, 222, 111, 222 ] }
7.$addToSet 数组操作
#增加一个值到数组内,而且只有当这个值不在数组内才增加 #插入2次发现,此值存在的时候不插入
> db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111, 222, 111, 222, [ 111, 222 ] ] } > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111, 222, 111, 222, [ 111, 222 ] ] } > db.array.update({'name':'laoda','age':65},{$addToSet:{"phone":333}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111, 222, 111, 222, [ 111, 222 ], 333 ] } > db.array.update({'name':'laoda','age':65},{$addToSet:{"phone":333}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 0 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111, 222, 111, 222, [ 111, 222 ], 333 ] }
8.$pop 删除数组内的一个值
#删除最后一个值:{ $pop : { field : 1 } }删除第一个值:{ $pop : { field : -1 } }
注意,只能删除一个值,也就是说只能用1或-1,而不能用2或-2来删除两条
> db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111, 222, 111, 222, [ 111, 222 ], 333 ] } > db.array.update({'name':'laoda','age':65},{$pop:{"phone":1}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111, 222, 111, 222, [ 111, 222 ] ] } > db.array.update({'name':'laoda','age':65},{$pop:{"phone":-1}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 222, 111, 222, [ 111, 222 ] ] } > db.array.update({'name':'laoda','age':65},{$pop:{"phone":2}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 222, 111, 222 ] } > db.array.update({'name':'laoda','age':65},{$pop:{"phone":333}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 222, 111 ] } > db.array.update({'name':'laoda','age':65},{$pop:{"phone":-333}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111 ] }
#测试发现,只要是正整数从最后删除,负数从头部删除。
9.$pull 数组field内删除一个等于value值
> db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111, 333 ] } > db.array.update({'name':'laoda','age':65},{$pull:{"phone":333}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111 ] }
10.$pullAll 数组field内删除多个值
> db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 111, 333, 222 ] } > db.array.update({'name':'laoda','age':65},{$pullAll:{"phone":[111,222]}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.array.find({},{'_id':0}) { "age" : 65, "name" : "laoda", "phone" : [ 333 ] }

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