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Best way to test if a row exists in a MySQL table
...OM test WHERE text LIKE '%something%'
LIMIT 1) : 0.044898986816406s.
But now, with a BIGINT PK field, only one entry is equal to '321321' :
SELECT * FROM test2 WHERE id ='321321' LIMIT 1 with
mysql_num_rows() : 0.0089840888977051s.
SELECT count(*) as count FROM test2 WHERE id ='321321' : 0.0003...
Difference between private, public, and protected inheritance
...like to describe member's accessors first in my own words. If you already know this, skip to the heading "next:".
There are three accessors that I'm aware of: public, protected and private.
Let:
class Base {
public:
int publicMember;
protected:
int protectedMember;
pr...
List of lists changes reflected across sublists unexpectedly
...than a matrix = [row] * 2 where both rows are exactly the same object, and now changes to one row matrix[0][0] = y suddenly reflect in the other one (matrix[0][0] is matrix[1][0]) == True
– nadrimajstor
Jul 2 '17 at 15:44
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Is there an exponent operator in C#?
... @Justas I just testing that on .NET Core 2.1 and Math.Pow is now faster than the suggested alternative implementation.
– bytedev
Dec 19 '18 at 11:19
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How should I organize Python source code? [closed]
...
Unfortunately the article is a dead link now :-(. The latest archived version is here: web.archive.org/web/20190714164001/http://…
– Igor Brejc
Apr 1 at 4:10
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What is a non-capturing group in regular expressions?
...tp://stackoverflow.com/
https://stackoverflow.com/questions/tagged/regex
Now, if I apply the regex below over it...
(https?|ftp)://([^/\r\n]+)(/[^\r\n]*)?
... I would get the following result:
Match "http://stackoverflow.com/"
Group 1: "http"
Group 2: "stackoverflow.com"
Group 3...
How to 'bulk update' with Django?
...
Update:
Django 2.2 version now has a bulk_update.
Old answer:
Refer to the following django documentation section
Updating multiple objects at once
In short you should be able to use:
ModelClass.objects.filter(name='bar').update(name="foo")
...
When do we need curly braces around shell variables?
...
{} is known as brace expansion. ${} is known as variable expansion. They do different things. I'd upvote you except for the no expansion bit.
– Spencer Rathbun
Jan 5 '12 at 21:52
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Why do you have to call .items() when iterating over a dictionary in Python?
...hen would you ever write a condition like this?
if (key, value) in dict:
Now it's not necessary that the in operator and for ... in operate over the same items. Implementation-wise they are different operations (__contains__ vs. __iter__). But that little inconsistency would be somewhat confusing ...
NodeJS: How to get the server's port?
...
Express 4.x answer:
Express 4.x (per Tien Do's answer below), now treats app.listen() as an asynchronous operation, so listener.address() will only return data inside of app.listen()'s callback:
var app = require('express')();
var listener = app.listen(8888, function(){
console.lo...