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MYSQL OR vs IN performance
...than using OR.
Do not believe people who give their "opinion", science is all about testing and evidence.
I ran a loop of 1000x the equivalent queries (for consistency, I used sql_no_cache):
IN: 2.34969592094s
OR: 5.83781504631s
Update:
(I don't have the source code for the original test, as it...
Image fingerprint to compare similarity of many images
...d approach for improved comparison quality
A luminosity histogram (especially one that is separated into RGB components) is a reasonable fingerprint for an image - and can be implemented quite efficiently. Subtracting one histogram from another will produce a new historgram which you can process t...
doesn't inherit the font from
...
@diEcho, this is true for all elements besides form elements, which inherit from the current system styling so they maintain a feel that is familiar to the user (by default), but they are manually overridable.
– Gabriele Petrioli...
Using margin:auto to vertically-align a div
So I know we can center a div horizontally if we use margin:0 auto; . Should margin:auto auto; work how I think it should work? Centering it vertically as well?
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Set 4 Space Indent in Emacs in Text Mode
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Is there really nothing shorter than '(tab-stop-list (quote (4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72 76 80 84 88 92 96 100 104 108 112 116 120)))? Well, as long as it works I guess... :P
– HelloGoodbye
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How to get screen dimensions as pixels in Android
I created some custom elements, and I want to programmatically place them to the upper right corner ( n pixels from the top edge and m pixels from the right edge). Therefore I need to get the screen width and screen height and then set position:
...
What is the HTML tabindex attribute?
... to set the order but just make your element focusable use tabindex="0" on all such elements:
<div tabindex="0"></div>
Also, if you don't want it to be focusable via the tab key then use tabindex="-1". For example, the below link will not be focused while using tab keys to traverse.
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How do I undo 'git add' before commit?
...ing anything else.
You can use
git reset
without any file name to unstage all due changes. This can come in handy when there are too many files to be listed one by one in a reasonable amount of time.
In old versions of Git, the above commands are equivalent to git reset HEAD <file> and git re...
Exposing a port on a live Docker container
...e -p flag with docker run to assign ports, but once a container is actually running, is there a command to open/map additional ports live?
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Elements order in a “for (… in …)” loop
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Quoting John Resig:
Currently all major browsers loop over the properties of an object in the order in
which they were defined. Chrome does this as well, except for a couple cases. [...]
This behavior is explicitly left undefined by the ECMAScript specifi...