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Is there any performance gain in indexing a boolean field?
... think about it like a book. If there were only 3 kinds of words in a book and you index all of them, you would have the same number of index pages as normal pages.
There would be a performance gain if there are relatively few records of one value. For example, if you have 1000 records and 10 of t...
What are the dark corners of Vim your mom never told you about? [closed]
... questions where people talk about common tricks, notably " Vim+ctags tips and tricks ".
70 Answers
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How do I get the width and height of a HTML5 canvas?
How can i get the width and height of the canvas element in JavaScript?
8 Answers
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Optimistic vs. Pessimistic locking
I understand the differences between optimistic and pessimistic locking. Now could someone explain to me when I would use either one in general?
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When writing a directive in AngularJS, how do I decide if I need no new scope, a new child scope, or
...omething similar to a flowchart that walks me through a bunch of questions and out pops the correct answer – no new new scope, new child scope, or new isolate scope – but that is likely asking for too much. Here's my current paltry set of guidelines:
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Which characters make a URL invalid?
...s above: /^[!#$&-;=?-[]_a-z~]+$/
– Leif Wickland
Oct 7 '11 at 17:01
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Activity restart on rotation Android
In my Android application, when I rotate the device (slide out the keyboard) then my Activity is restarted ( onCreate is called). Now, this is probably how it's supposed to be, but I do a lot of initial setting up in the onCreate method, so I need either:
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How to get the current date/time in Java [duplicate]
...UNIX epoch (as a Java long). This value is a delta from a UTC time-point, and is independent of the local time-zone ... assuming that the system clock has been set correctly.
If you want the date / time in a form that allows you to access the components (year, month, etc) numerically, you could use...
Abusing the algebra of algebraic data types - why does this work?
...ely, all unit types. They behave identically under algebraic manipulations and, more importantly, the amount of information present is still preserved.
You probably want a zero type as well. Haskell provides that as Void. There are no values whose type is zero, just as there is one value whose type ...
Using Phonegap for Native Application development [closed]
...ch claims that developers can use HTML 5 based framework like Sencha touch and Jquery at the same time
having access to native features on phone. Also the code is portable from Android to Iphone with some effort. Before I plunge into it I want to know what is forum's experience with Phonegap. What ...