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How to design a database for User Defined Fields?
...define the data domains. Don't underestimate the performance hit resulting from on-the-fly data type conversion. Such
constraints also help RDBMS query
optimizers develop more effective
plans.
Should you ever need to use foreign
keys, built-in declarative
referential
integrity is rarely out-per...
Using querySelector with IDs that are numbers
From what I understand the HTML5 spec lets you use IDs that are numbers like this.
5 Answers
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How do you return from 'gf' in Vim
I am using Vim for windows installed in Unix mode. Thanks to this site I now use the gf command to go to a file under the cursor.
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Fade/dissolve when changing UIImageView's image
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Edit: there is a better solution from @algal below.
Another way to do this is by using predefined CAAnimation transitions:
CATransition *transition = [CATransition animation];
transition.duration = 0.25;
transition.timingFunction = [CAMediaTimingFunction f...
Why do this() and super() have to be the first statement in a constructor?
... for you automatically by the compiler. Since every class in Java inherits from Object, objects constructor must be called somehow and it must be executed first. The automatic insertion of super() by the compiler allows this. Enforcing super to appear first, enforces that constructor bodies are exec...
What are the reasons why Map.get(Object key) is not (fully) generic
...specification of the method only requires that they be equal. This follows from how the equals() method takes in an Object as parameter, not just the same type as the object.
Although it may be commonly true that many classes have equals() defined so that its objects can only be equal to objects of...
How to force a view refresh without having it trigger automatically from an observable?
...7397%2fhow-to-force-a-view-refresh-without-having-it-trigger-automatically-from-an-obse%23new-answer', 'question_page');
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);
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Name
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Is a Java string really immutable?
...e's some suggested further reading: Heinz Kabutz's Reflection Madness talk from JavaZone 2009, which covers a lot of the issues in the OP, along with other reflection... well... madness.
It covers why this is sometimes useful. And why, most of the time, you should avoid it. :-)
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JavaScript closures vs. anonymous functions
...nterested in identifying a subset of these functions which are interesting from a theoretical point of view. Henceforth any reference to the word closure will refer to this subset of functions unless otherwise stated.
A simple explanation for closures:
Take a function. Let's call it F.
List all t...
Accessing bash command line args $@ vs $*
...
A nice handy overview table from the Bash Hackers Wiki:
where c in the third row is the first character of $IFS, the Internal Field Separator, a shell variable.
If the arguments are to be stored in a script variable and the arguments are expected to...