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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...cit, so you can get away with a slightly dumber optimizer.
When in doubt, test!
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Why is there a difference in checking null against a value in VB.NET and C#?
...e by an unfortunate belief that it is confusing to have different means of testing equality yield different results, and such confusion might be avoided by having the different forms of equality yield the same results whenever possible.
In reality, the fundamental cause of confusion is a misguided ...
Enable access control on simple HTTP server
.../env python3
from http.server import HTTPServer, SimpleHTTPRequestHandler, test
import sys
class CORSRequestHandler (SimpleHTTPRequestHandler):
def end_headers (self):
self.send_header('Access-Control-Allow-Origin', '*')
SimpleHTTPRequestHandler.end_headers(self)
if __name__ ==...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...start transaction; create temporary table temporary_table as select * from test where false; copy temporary_table from 'data_file.csv'; lock table test; update test set data=temporary_table.data from temporary_table where test.id=temporary_table.id; insert into test select * from temporary_table whe...
git ahead/behind info between master and branch?
I have created a branch for testing in my local repo ( test-branch ) which I pushed to Github .
5 Answers
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Best way to work with transactions in MS SQL Server Management Studio
...nt that you can also (and should if what you are writing is complex) add a test variable to rollback if you are in test mode. Then you can execute the whole thing at once. Often I also add code to see the before and after results of various operations especially if it is a complex script.
Example ...
Performance difference between IIf() and If
...de effects.
Code illustration:
Module Module1
Sub Main()
Dim test As Boolean = False
Dim result As String = IIf(test, Foo(), Bar())
End Sub
Public Function Foo() As String
Console.WriteLine("Foo!")
Return "Foo"
End Function
Public Function Bar(...
When is a Java method name too long? [closed]
...ot be too long. I do want to add one exception though:
The names of JUnit test methods, however, can be long and should resemble sentences.
Why?
Because they are not called in other code.
Because they are used as test names.
Because they then can be written as sentences describing requirements. ...
Regular expression for first and last name
...upports some special characters like hyphens, spaces and apostrophes. I've tested in python and it supports the characters below:
^[\w'\-,.][^0-9_!¡?÷?¿/\\+=@#$%ˆ&*(){}|~<>;:[\]]{2,}$
Characters supported:
abcdefghijklmnopqrstwxyz
ABCDEFGHIJKLMNOPQRSTUVWXYZ
áéíóúäëïöüÄ'
...
PDO's query vs execute
...metimes there are rare exceptions to best practices, and you might want to test your environment both ways to see what will work best.
In one case, I found that query worked faster for my purposes because I was bulk transferring trusted data from an Ubuntu Linux box running PHP7 with the poorly sup...