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ROW_NUMBER() in MySQL
...solution is basically the same as if someone would try to find the largest id with the following query: SELECT t1.id FROM test t1 LEFT JOIN test t2 ON t1.id>t2.id WHERE t2.id IS NULL; Does not it require n*n/2 + n/2 IS NULL comparisons to find the single row? Do there happen any optimizations I d...
WebAPI Delete not working - 405 Method Not Allowed
... add the following to your web.config
<system.webServer>
<validation validateIntegratedModeConfiguration="false"/>
<modules runAllManagedModulesForAllRequests="true">
<remove name="WebDAVModule"/> <!-- ADD THIS -->
</modules>
... rest of s...
Capture Image from Camera and Display in Activity
... image and display it.
package edu.gvsu.cis.masl.camerademo;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
public class MyCameraActivity...
android:drawableLeft margin and/or padding
...e to set the margin or padding for the image which we added with the android:drawableLeft ?
18 Answers
...
How can I make space between two buttons in same div?
...
Put them inside btn-toolbar or some other container, not btn-group. btn-group joins them together. More info on Bootstrap documentation.
Edit: The original question was for Bootstrap 2.x, but the same is still valid for Bootstrap 3 and ...
Specifying column name in a “references” migration
...
Do it manually:
add_column :post, :author_id, :integer
but now, when you create the belongs_to statement, you will have to modify it, so now you have to call
def post
belongs_to :user, :foreign_key => 'author_id'
end
...
搭建高可用mongodb集群（四）—— 分片 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...001
#使用admin数据库
use admin
#定义副本集配置
config = { _id:"shard1", members:[
{_id:0,host:"192.168.0.136:22001"},
{_id:1,host:"192.168.0.137:22001"},
{_id:2,host:"192.168.0.138:22001",arbiterOnly:true}
...
How to declare a type as nullable in TypeScript?
...Union type is in my mind best option in this case:
interface Employee{
id: number;
name: string;
salary: number | null;
}
// Both cases are valid
let employe1: Employee = { id: 1, name: 'John', salary: 100 };
let employe2: Employee = { id: 1, name: 'John', salary: null };
EDIT : For thi...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...
You can add ORDER BY NULL to the GROUP BY to avoid the sort.
– Ariel
Aug 20 '14 at 3:21
Sti...
How to report an error from a SQL Server user-defined function
...ull, and in my case I wanted to throw an error when nothing was found. I didn't want to break down the inline function into a multi-statment one for obvious performance reasons. Instead I used your solution plus ISNULL and MAX. The RETURN statment now looks like this: SELECT ISNULL(MAX(E.EntityID...