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MongoDB SELECT COUNT GROUP BY
...er way to do it using aggregate:
db.contest.aggregate([
{"$group" : {_id:"$province", count:{$sum:1}}}
])
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How do I make and use a Queue in Objective-C?
...tableArray+QueueAdditions.h
@interface NSMutableArray (QueueAdditions)
- (id) dequeue;
- (void) enqueue:(id)obj;
@end
NSMutableArray+QueueAdditions.m
@implementation NSMutableArray (QueueAdditions)
// Queues are first-in-first-out, so we remove objects from the head
- (id) dequeue {
// if ([...
Submitting HTML form using Jquery AJAX
...ituations JSON). Because we are doing an ASYNC task we will likely be providing our users with a more enjoyable UI experience. In this specific case we are doing a FORM submission using AJAX.
Really quickly there are 4 general web actions GET, POST, PUT, and DELETE; these directly correspond with ...
How to record webcam and audio using webRTC and a server-based Peer connection
...
You should definitely have a look at Kurento. It provides a WebRTC server infrastructure that allows you to record from a WebRTC feed and much more. You can also find some examples for the application you are planning here. It is really easy to add recording capabilities to tha...
Why switch is faster than if
...he switch statement as being faster than the if else statement. But I did not find out anywhere why switch is faster than if .
...
What is meaning of boolean value returned from an event-handling method in Android
In android, most event listener methods return a boolean value. What is that true/false value mean ? what will it result in to the subsequence events ?
...
How to use GROUP_CONCAT in a CONCAT in MySQL
...
select id, group_concat(`Name` separator ',') as `ColumnName`
from
(
select
id,
concat(`Name`, ':', group_concat(`Value` separator ',')) as `Name`
from mytbl
group by
id,
`Name`
) tbl
group by id;
You can...
Join/Where with LINQ and Lambda
...ax is much clearer, more natural, and makes it easier to spot errors:
var id = 1;
var query =
from post in database.Posts
join meta in database.Post_Metas on post.ID equals meta.Post_ID
where post.ID == id
select new { Post = post, Meta = meta };
If you're really stuck on using lambda...
Entity Framework Migrations renaming tables and columns
...rything, including the foreign keys with the new column name.
public override void Up()
{
RenameTable("ReportSections", "ReportPages");
RenameTable("ReportSectionGroups", "ReportSections");
RenameColumn("ReportPages", "Group_Id", "Section_Id");
}
public override void Down()
{
Renam...
Show and hide a View with a slide up/down animation
I have a LinearLayout that I want to show or hide with an Animation that pushes the layout upwards or downwards whenever I change its visibility.
...