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Are there disadvantages to using a generic varchar(255) for all text-based fields?
...se Ruby on Rails migrations map String fields to VARCHAR(255) by default and I never bothered to override it).
7 Answer...
Difference between binary semaphore and mutex
Is there any difference between a binary semaphore and mutex or are they essentially the same?
34 Answers
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Function overloading by return type?
...Contrary to what others are saying, overloading by return type is possible and is done by some modern languages. The usual objection is that in code like
int func();
string func();
int main() { func(); }
you can't tell which func() is being called. This can be resolved in a few ways:
Have a p...
Delete all local changesets and revert to tree
I'm using Mercurial and I've got into a terrible mess locally, with three heads. I can't push, and I just want to delete all my local changes and commits and start again with totally clean code and a clean history.
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Difference between Inheritance and Composition
Are Composition and Inheritance the same?
If I want to implement the composition pattern, how can I do that in Java?
17 Ans...
Can the Android layout folder contain subfolders?
...ng every XML layout file inside the 'res/layout' folder, so it is feasible and simple to manage small projects, but when there is a case of large and heavy projects, then there should be a hierarchy and sub-folders needed inside the layout folder.
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Developing cross platform mobile application [closed]
More and more mobile platforms are being launched and sdk's are available to developers. There are various mobile platform are available:
Android, iOS, Moblin, Windows mobile 7, RIM, symbian, bada, maemo etc.
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MySQL: multiple tables or one table with many columns?
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Any time information is one-to-one (each user has one name and password), then it's probably better to have it one table, since it reduces the number of joins the database will need to do to retrieve results. I think some databases have a limit on the number of columns per table, but...
Why does Python print unicode characters when the default encoding is ASCII?
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Thanks to bits and pieces from various replies, I think we can stitch up an explanation.
By trying to print an unicode string, u'\xe9', Python implicitly try to encode that string using the encoding scheme currently stored in sys.stdout.e...
Is JavaScript a pass-by-reference or pass-by-value language?
...er that a variable holding an object is in fact a reference to the object) and passed-by-reference (when we consider that the variable to the object holds the object itself).
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