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Database development mistakes made by application developers [closed]
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1. Not using appropriate indices
This is a relatively easy one but still it happens all the time. Foreign keys should have indexes on them. If you're using a field in a WHERE you should (probably) have an index on it. Such indexes should often cover multiple columns based on the queries you nee...
Is it correct to use alt tag for an anchor link?
Is it correct to use alt tag for an anchor link, something like
7 Answers
7
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How do you build a Singleton in Dart?
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Thanks to Dart's factory constructors, it's easy to build a singleton:
class Singleton {
static final Singleton _singleton = Singleton._internal();
factory Singleton() {
return _singleton;
}
Singleton._internal();
}
You can construct it like this
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Regex Last occurrence?
...the last part after the last backslash
I need the \Web_ERP_Assistant (with the \ )
7 Answers
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Objective-C categories in static library
...go to the application that is linking against the library (not the library itself) and click the project in the Project Navigator, click your app's target, then build settings, then search for "Other Linker Flags", click the + button, and add '-ObjC'. '-all_load' and '-force_load' are no longer need...
Why do browsers match CSS selectors from right to left?
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Keep in mind that when a browser is doing selector matching it has one element (the one it's trying to determine style for) and all your rules and their selectors and it needs to find which rules match the element. This is different from the usual jQuery thing, say, where you only ha...
When is JavaScript's eval() not evil?
I'm writing some JavaScript code to parse user-entered functions (for spreadsheet-like functionality). Having parsed the formula I could convert it into JavaScript and run eval() on it to yield the result.
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Is there a goto statement in Java?
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The Java keyword list specifies the goto keyword, but it is marked as "not used".
It was in the original JVM (see answer by @VitaliiFedorenko), but then removed. It was probably kept as a reserved keyword in case it were to be added to a later version of Java.
If goto was not ...
What is an ORM, how does it work, and how should I use one? [closed]
...ect that I'm designing, but I'm having trouble finding information on what it is or how it works.
5 Answers
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Why is the String class declared final in Java?
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It is very useful to have strings implemented as immutable objects. You should read about immutability to understand more about it.
One advantage of immutable objects is that
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