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mongodb入门-7查询2

mongodb入门-7查询2
 
数组查询$all $in
 
$all 数组中必须包含所有给定的查询的元素
 
$in 数组中只要包含给定的查询元素就可以
 
下面看两个代码:
 
[html] 
> db.phone.find()  
{ "_id" : ObjectId("5198e20220c9b0dc40419385"), "num" : [ 1, 2, 3 ] }  
{ "_id" : ObjectId("5198e21820c9b0dc40419386"), "num" : [ 4, 2, 3 ] }  
{ "_id" : ObjectId("5198e22120c9b0dc40419387"), "num" : [ 1, 2, 5 ] }  
> db.phone.find({num:{$all:[1,2]}})  
{ "_id" : ObjectId("5198e20220c9b0dc40419385"), "num" : [ 1, 2, 3 ] }  
{ "_id" : ObjectId("5198e22120c9b0dc40419387"), "num" : [ 1, 2, 5 ] }  
> db.phone.find({num:{$all:[1,4]}}) --->同时包含1,4的没有数据  
> db.phone.find({num:{$in:[1,4]}}) --->包含1或4的数据  
{ "_id" : ObjectId("5198e20220c9b0dc40419385"), "num" : [ 1, 2, 3 ] }  
{ "_id" : ObjectId("5198e21820c9b0dc40419386"), "num" : [ 4, 2, 3 ] }  
{ "_id" : ObjectId("5198e22120c9b0dc40419387"), "num" : [ 1, 2, 5 ] }  
 
$exists 查找包含该字段的文档
一段代码如下:
 
[html] 
> db.phone.find()  
{ "_id" : ObjectId("5198e20220c9b0dc40419385"), "num" : [ 1, 2, 3 ] }  
{ "_id" : ObjectId("5198e21820c9b0dc40419386"), "num" : [ 4, 2, 3 ] }  
{ "_id" : ObjectId("5198e22120c9b0dc40419387"), "num" : [ 1, 2, 5 ] }  
{ "_id" : ObjectId("5198e51a20c9b0dc40419388"), "state" : 1 }  
> db.phone.find({state:{$exists:1}}) --->存在state字段的  
{ "_id" : ObjectId("5198e51a20c9b0dc40419388"), "state" : 1 }  
> db.phone.find({state:{$exists:0}}) --->不存在state字段的文档  
{ "_id" : ObjectId("5198e20220c9b0dc40419385"), "num" : [ 1, 2, 3 ] }  
{ "_id" : ObjectId("5198e21820c9b0dc40419386"), "num" : [ 4, 2, 3 ] }  
{ "_id" : ObjectId("5198e22120c9b0dc40419387"), "num" : [ 1, 2, 5 ] }  
 
$mod 取模操作
比如我们可以取一些数据的时候做一些模操作,比如向下面一样取年龄模3余1的文档:
 
[html] 
> db.user.find()  
{ "_id" : ObjectId("5198c286c686eb50e2c843b2"), "name" : "user0", "age" : 0 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b3"), "name" : "user1", "age" : 1 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b4"), "name" : "user2", "age" : 2 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b5"), "name" : "user3", "age" : 3 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b6"), "name" : "user4", "age" : 4 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b7"), "name" : "user5", "age" : 5 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b8"), "name" : "user6", "age" : 6 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b9"), "name" : "user7", "age" : 7 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843ba"), "name" : "user8", "age" : 8 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843bb"), "name" : "user9", "age" : 9 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843bc"), "name" : "user10", "age" : 10 }  
{ "_id" : ObjectId("5198c3cac686eb50e2c843bd"), "name" : "user0", "age" : 20 }  
> db.user.find({age:{$mod:[3,1]}})   
{ "_id" : ObjectId("5198c286c686eb50e2c843b3"), "name" : "user1", "age" : 1 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b6"), "name" : "user4", "age" : 4 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b9"), "name" : "user7", "age" : 7 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843bc"), "name" : "user10", "age" : 10 }  
 
同样使用 db.user.find("this.age%3==1")这个语句也能达到上面的效果,但是不推荐.
 
$ne not equal 不等于
 
查找age不等于0的用户:
 
[html] 
> db.user.find()  
{ "_id" : ObjectId("5198c286c686eb50e2c843b2"), "name" : "user0", "age" : 0 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b3"), "name" : "user1", "age" : 1 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b4"), "name" : "user2", "age" : 2 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b5"), "name" : "user3", "age" : 3 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b6"), "name" : "user4", "age" : 4 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b7"), "name" : "user5", "age" : 5 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b8"), "name" : "user6", "age" : 6 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b9"), "name" : "user7", "age" : 7 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843ba"), "name" : "user8", "age" : 8 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843bb"), "name" : "user9", "age" : 9 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843bc"), "name" : "user10", "age" : 10 }  
{ "_id" : ObjectId("5198c3cac686eb50e2c843bd"), "name" : "user0", "age" : 20 }  
> db.user.find({age:{$ne:0}})  
{ "_id" : ObjectId("5198c286c686eb50e2c843b3"), "name" : "user1", "age" : 1 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b4"), "name" : "user2", "age" : 2 }  
{ "_id" : ObjectId("5198c286c686eb50e2c843b5"), "name" : "user3", "age" : 3 }  
{ "_id" : ObjectId("5198c286c686eb50e2c8
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