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How to use GROUP_CONCAT in a CONCAT in MySQL
...what you need.
Update
Splitting in two steps. First we get a table having all values(comma separated) against a unique[Name,id]. Then from obtained table we get all names and values as a single value against each unique id
See this explained here SQL Fiddle Demo (scroll down as it has two result se...
How to handle click event in Button Column in Datagridview?
... a single button per grid, you can jump right off to the races.
Putting it all together:
C#:
private void dataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e)
{
var senderGrid = (DataGridView)sender;
if (senderGrid.Columns[e.ColumnIndex] is DataGridViewButtonColumn &am...
demystify Flask app.secret_key
If app.secret_key isn't set, Flask will not allow you to set or access the session dictionary.
2 Answers
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How can I write output from a unit test?
Any call in my unit tests to either Debug.Write(line) or Console.Write(Line) simply gets skipped over while debugging and the output is never printed. Calls to these functions from within classes I'm using work fine.
...
What's the fastest algorithm for sorting a linked list?
...; there are no pathological cases.
Auxiliary storage requirement is small and constant (i.e. a few variables within the sorting routine). Thanks to the inherently different behaviour of linked lists from arrays, this Mergesort implementation avoids the O(N) auxiliary storage cost normally assoc...
How can I use Timer (formerly NSTimer) in Swift?
...syntax (iOS 10+)
let timer = Timer(timeInterval: 0.4, repeats: true) { _ in print("Done!") }
// Swift >=3 selector syntax
let timer = Timer.scheduledTimer(timeInterval: 0.4, target: self, selector: #selector(self.update), userInfo: nil, repeats: true)
// Swift 2.2 selector syntax
...
Unicode equivalents for \w and \b in Java regular expressions?
...cter class shorthand as "any letter, digit, or connecting punctuation" (usually: underscore). That way, a regex like \w+ matches words like hello , élève , GOÄ_432 or gefräßig .
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Best way to serialize an NSData into a hexadeximal string
...rsion.h
#import <Foundation/Foundation.h>
@interface NSData (NSData_Conversion)
#pragma mark - String Conversion
- (NSString *)hexadecimalString;
@end
NSData+Conversion.m
#import "NSData+Conversion.h"
@implementation NSData (NSData_Conversion)
#pragma mark - String Conversion
- (NSStr...
How exactly does the callstack work?
...ng of how the low level operations of programming languages work and especially how they interact with the OS/CPU. I've probably read every answer in every stack/heap related thread here on Stack Overflow, and they are all brilliant. But there is still one thing that I didn't fully understand yet.
...
Google Chrome form autofill and its yellow background
...mages behind your input field just fill the whole area with white. I tried all the solutions on this page, including the jquery based ones and they didnt work for me, in the end i had to add autocomplete="off" to the field.
– Myke Black
Mar 28 '14 at 15:05
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