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IN vs OR in the SQL WHERE Clause
...rding to the manual for MySQL if the values are constant IN sorts the list and then uses a binary search. I would imagine that OR evaluates them one by one in no particular order. So IN is faster in some circumstances.
The best way to know is to profile both on your database with your specific dat...
CSS “and” and “or”
... Ok, thanks for light. I hate styling forms, but it's my task, and site isn't mine. I'll apply classes to inputs.
– Misiur
May 9 '10 at 9:02
5
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Which characters need to be escaped in HTML?
...d in XML. Inside of an element, this just includes the entity escape ampersand & and the element delimiter less-than and greater-than signs < >:
& becomes &amp;
< becomes &lt;
> becomes &gt;
Inside of attribute values you must also escape the quote character you're ...
What is the difference between linear regression and logistic regression?
...ut as probabilities but it's a mistake because the output can be negative, and greater than 1 whereas probability can not. As regression might actually
produce probabilities that could be less than 0, or even bigger than
1, logistic regression was introduced.
Source: http://gerardnico.com/wiki/dat...
How do I make a redirect in PHP?
...it(): The Daily WTF
Absolute or relative URL
Since June 2014 both absolute and relative URLs can be used. See RFC 7231 which had replaced the old RFC 2616, where only absolute URLs were allowed.
Status Codes
PHP's "Location"-header still uses the HTTP 302-redirect code, this is a "temporary" redirec...
How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
How can I use regular expressions in Excel and take advantage of Excel's powerful grid-like setup for data manipulation?
9 ...
Need some clarification about beta/alpha testing on the developer console
The Android developer console has 3 tabs for publishing the app's apk file:
alpha, beta and production, as shown here:
4 An...
Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding
...e with an ATmega328 . I am working on Ubuntu 12.04 (Precise Pangolin), and the Arduino IDE's version is 1.0. Recently, I tried to upload a few of the sample sketches onto it, such as the Blink one. However, none of my attempts are working and they result in the same error every time I try it:
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How can I test a Windows DLL file to determine if it is 32 bit or 64 bit? [duplicate]
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Gory details
A DLL uses the PE executable format, and it's not too tricky to read that information out of the file.
See this MSDN article on the PE File Format for an overview. You need to read the MS-DOS header, then read the IMAGE_NT_HEADERS structure. This contains the I...
What is the difference between gravity and layout_gravity in Android?
I know we can set the following values to the android:gravity and android:layout_gravity properties:
20 Answers
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