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SQL left join vs multiple tables on FROM line?
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The old syntax, with just listing the tables, and using the WHERE clause to specify the join criteria, is being deprecated in most modern databases.
It's not just for show, the old syntax has the possibility of being ambiguous when you use b...
What is the difference between a function expression vs declaration in JavaScript? [duplicate]
...hes that line of code.
So if you try to call a function expression before it's loaded, you'll get an error! If you call a function declaration instead, it'll always work, because no code can be called until all declarations are loaded.
Example: Function Expression
alert(foo()); // ERROR! foo was...
How does the vim “write with sudo” trick work?
Many of you have probably seen the command that allows you to write on a file that needs root permission, even when you forgot to open vim with sudo:
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Is Using .NET 4.0 Tuples in my C# Code a Poor Design Decision?
With the addition of the Tuple class in .net 4, I have been trying to decide if using them in my design is a bad choice or not. The way I see it, a Tuple can be a shortcut to writing a result class (I am sure there are other uses too).
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Is there a Java reflection utility to do a deep comparison of two objects?
I'm trying to write unit tests for a variety of clone() operations inside a large project and I'm wondering if there is an existing class somewhere that is capable of taking two objects of the same type, doing a deep comparison, and saying if they're identical or not?
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What does $.when.apply($, someArray) do?
...and Promises and keep coming across $.when.apply($, someArray) . I'm a little unclear on what this does exactly, looking for an explanation that one line works exactly (not the entire code snippet). Here's some context:
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Create ArrayList from array
I have an array that is initialized like:
38 Answers
38
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versionCode vs versionName in Android Manifest
I had my app in the android market with version code = 2 and version name = 1.1
10 Answers
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What are database normal forms and can you give examples? [closed]
...s) and tables (relations) to reduce data redundancy and improve data integrity. (as written on Wikipedia ).
4 Answers
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Check if object exists in JavaScript
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You can safely use the typeof operator on undefined variables.
If it has been assigned any value, including null, typeof will return something other than undefined. typeof always returns a string.
Therefore
if (typeof maybeObject != "undefined") {
alert("GOT THERE");
}
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