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Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
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Aha so by using * you are adding extra work for the DB. Ok that's one reason I hadn't thought of.
– Ankur
Jun 4 '10 at 6:50
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What is the maximum length of a valid email address?
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An email address must not exceed 254 characters.
This was accepted by the IETF following submitted erratum. A full diagnosis of any given address is available online. The original version of RFC 3696 described 320 as the maximum length, but John Klensin subsequ...
How to tell if a tag failed to load
...ISS IMHO).
From the spec:
If the src attribute's value is the
empty string or if it could not be
resolved, then the user agent must
queue a task to fire a simple event
named error at the element, and
abort these steps.
~
If the load resulted in an error (for
example a DNS erro...
Why are only final variables accessible in anonymous class?
...c final int a = 3;
or as a local variable, like
public static void main(String[] args)
{
final int a = 3;
If you want to access and modify a variable from an anonymous class, you might want to make the variable a class-level variable in the enclosing class.
public class Test
{
public int a;
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What is the most compatible way to install python modules on a Mac?
...r elixir
( make sure you always type pip-(version) )
That will build an extra Python library in your home dir. Yes, Python will work with more than one library location: one controlled by MacPorts and a user local one for everything missing within MacPorts.
Now notice that I favor pip over easy_...
Strange out of memory issue while loading an image to a Bitmap object
...);
int imageHeight = options.outHeight;
int imageWidth = options.outWidth;
String imageType = options.outMimeType;
To avoid java.lang.OutOfMemory exceptions, check the dimensions of a bitmap before decoding it, unless you absolutely trust the source to provide you with predictably sized image data...
Static linking vs dynamic linking
... require a some kind of glue layer which often means double dispatch or an extra layer of indirection in function addressing and can cost a little speed (but is function calling time actually a big part of your running time???).
However, if you are running multiple processes which all call the same...
How to pass event as argument to an inline event handler in JavaScript?
...ating data binding capabilities available in mainstream js frameworks. One extra trick is to do something similar to Object.assign(this.querySelector('my-btn'), this) inside a web component and voila, data binding. You can access any method of the parent web component class from the inline events on...
Transmitting newline character “\n”
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Try using %0A in the URL, just like you've used %20 instead of the space character.
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http HEAD vs GET performance
... answered Sep 3 '14 at 20:31
Charles ThomasCharles Thomas
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