MongoDB- query keywords / sorting

Search Keyword

$ And parallel query

# Are true before they can query the results 
db.stutent.find ({$ and : [{name: " little whirlpool " }, {Age: 30}]})

Or $ or queries

# There is a condition set up you can check the results 
db.stu.find ({$ or : [{name: " dazzling " }, {name: " black " }]})

Subqueries $ all

 The rear part of all elements of the order list, as long as there will be in the test_list all query results to

> db.stutent.find({"test_list":{$all:[1,"五"]}})

{ "_id" : ObjectId("5d2eee1314ff51d814e40365"), "name" : "小漩涡", "age" : 30, "test_list" : [ 1, 2, 3, 4, "五", 1000 ], "hobby" : [ "烫头" ] }

$ In range queries

[ " Dazzling " , " black " , " red " , " black " ]
 # meet all of the names in the list to find out 
db.stu.find ({name: {$ in : [ " dazzling " , " black black " , " red " , " black " ]}})

Sort / select / Skip

Sorting: Sort 
. Db.stu.find () Sort ({Age: . 1}). 1 n Preface - . 1 reverse 

select: limit 
db.stu.find () limit (. 2 ) Select two data 

Skip: Skip 
DB. . stu.find () skip ( 2 ) skip the first two data 

selecting among two or before the N skipped 
db.stu.find () skip (0) .limit (. 2) .sort ({Age: - 1 }) 

priority: first Sort - skip - select 

# tab 
var = 1 Page 
var NUM = 2 
var SK = (Page-1) * NUM 
db.stu.find () skip (SK) .limit (NUM). .sort ({Age: -1})