queries in mongodb command line -


i want query list cities in specific state populations between 6000 , 8000. in big data. :

{ "_id" : "01564", "city" : "sterling", "loc" : [ -71.775192, 42.435351 ], "pop" : 6481, "state" : "ma" } { "_id" : "01566", "city" : "sturbridge", "loc" : [ -72.084233, 42.112619 ], "pop" : 7001, "state" : "ma" } { "_id" : "01568", "city" : "west upton", "loc" : [ -71.608014, 42.173275 ], "pop" : 4682, "state" : "ma" } { "_id" : "01569", "city" : "uxbridge", "loc" : [ -71.632869, 42.074426 ], "pop" : 10364, "state" : "ma" }

i want return cities in massachusetts let above example. how can ? t tried :

 >db.zipcodes.aggregate( [    { $group: { _id: "$city",statename:"$state", totalpop: { $sum: "$pop" } } }, { $match: { totalpop: { $gte: 1000  , $lte : 2000 },statename:"massachusetts" } } ] );

and got error below: 

 aggregate failed @ error (<anonymous>) @ doassert (src/mongo/shell/assert.js:11:14) @ function.assert.commandworked (src/mongo/shell/assert.js:254:5) @ dbcollection.aggregate (src/mongo/shell/collection.js:1278:12) @ (shell):1:13 @ src/mongo/shell/assert.js:13

you not need use aggregation framework.

db.zipcodes.find({    state: 'ma',    pop: {      $gte: 6000,      $lte: 8000    } }, {city: 1})

if need name of cities (unique) can use distinct 

db.zipcodes.distinct('city', {    state: 'ma',    pop: {      $gte: 6000,      $lte: 8000    } })

or use foreach


Comments

Post a Comment

Popular posts from this blog

jquery - How do you format the date used in the popover widget title of FullCalendar? -

Image
in fullcalendar, how format date used in popover widget title when clicking '+n more'? code: <div class="fc-popover fc-more-popover"> <div class="fc-header fc-widget-header"> <span class="fc-close fc-icon fc-icon-x"></span> <span class="fc-title">tuesday, april 7</span> ... </div> ... </div> you use daypopoverformat that. determines date format of title of popover created eventlimitclick option. must date formatting string. default value "dddd, mmmm d" english , "ll" other languages.
Read more

Bubble Sort Manually a Linked List in Java -

Image
this first question here. trying manually sort linked list of integers in java , can not figure out wrong code. suggestions? don't error, still have output unordered. tried few different ways, nothing worked. appreciate if can me that. public class node { int data; node nextnode; public node(int data) { this.data = data; this.nextnode = null; } public int getdata() { return this.data; } } // node class public class datalinkedlist implements datainterface { private node head; private int size; public datalinkedlist(){ this.head = null; this.size = 0; } public void add(int data) { node node = new node(data); if (head == null) { head = node; } else { node currentnode = head; while(currentnode.nextnode != null) { currentnode = currentnode.nextnode; } currentnode.nextnode = node; ...
Read more

asp.net mvc - SSO between MVCForum and Umbraco7 -

i need integrate sso between mvcforum (forum of company) , umbraco7 (manages cms company). however struggling shared authentication work. tried several ways suggested on other threads still not running expected. here did: 1. in mvcforum (forum.mywebsite.com) 1.1. machine key in web.xml: <machinekey validationkey="the same key umbraco7" decryptionkey="the same key umbraco7" validation="sha1" decryption="aes" /> 1.2. authenticate forms in web.xml <forms name="my-sso-auth" protection="all" path="/" timeout="43200" domain="forum.mywebsite.com" loginurl="/members/logon" enablecrossappredirects="true" /> 2. in umbraco7 (news.mywebsite.com) 2.1. machine key in web.xml: <machinekey validationkey="the same key mvcforum" decryptionkey="the same key mvcforum" validation="sha1" decryption="aes" /> 2.2. a...
Read more