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PDO's query vs execute
...ment, and hopefully you can replicate it or something better in yours:
To start, I've created a basic table in Microsoft SQL Server
CREATE TABLE performancetest (
sid INT IDENTITY PRIMARY KEY,
id INT,
val VARCHAR(100)
);
And now a basic timed test for performance metrics.
$logs = []...
JOIN queries vs multiple queries
... depending on whether or not you're planning on scaling. Cuz when facebook started out I'm sure they had those kind of queries, but had scaling in mind and went for the more efficient albeit possibly more complex solution.
– dudewad
Jul 4 '13 at 23:04
...
Correct way to use StringBuilder in SQL
... listed some_appropriate_size in the StringBuilder constructor, so that it starts out with enough capacity for the full content we're going to append. The default size used if you don't specify one is 16 characters, which is usually too small and results in the StringBuilder having to do reallocatio...
Copy folder structure (without files) from one location to another
... xargs can exceed the maximum command length of the system when you start dealing with orders of hundreds or thousands, so use this with caution. (Find the command length limit with getconf ARG_MAX.) With a lot of directories, you may have to write a script to loop through the output instead....
Simultaneously merge multiple data.frames in a list
...e all columns, we can use select helpers from tidyselect and
choose (as we start from .x all .x columns are kept):
eat(x, list(y,z), starts_with("l") ,.by = "i")
# # A tibble: 3 x 3
# i j l
# <chr> <int> <int>
# 1 a 1 9
# 2 b 2 NA
# 3 c ...
How to call asynchronous method from synchronous method in C#?
...then you'll deadlock even with the nested context. In that case, you could start the async method on the thread pool:
var task = Task.Run(async () => await MyAsyncMethod());
var result = task.WaitAndUnwrapException();
However, this solution requires a MyAsyncMethod that will work in the thread p...
How to center a (background) image within a div?
...e background-position property .
The background-position property sets the starting position of a background image from top and left sides of the element .
The CSS Syntax is background-position : xvalue yvalue; .
"xvalue" and "yvalue" supported values are length units like px and percentage and dir...
How do I get the dialer to open with phone number displayed?
...
Two ways to achieve it.
1) Need to start the dialer via code, without user interaction.
You need Action_Dial,
use below code it will open Dialer with number specified
Intent intent = new Intent(Intent.ACTION_DIAL);
intent.setData(Uri.parse("tel:0123456789"));...
Push Notifications in Android Platform
...ion - Does Android support near real time push notification? )
I recently started playing with MQTT http://mqtt.org for Android as a way of doing this sort of thing (i.e. push notification that is not SMS but data driven, almost immediate message delivery, not polling, etc.)
I have a blog post wit...
How do I get the day of the week with Foundation?
...atter weekdaySymbols] (and similar), which returns an NSArray of NSStrings starting with Sunday at index 0.
– beetstra
Nov 9 '11 at 12:18
...