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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...
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...
How can I do a line break (line continuation) in Python?
...g line of code that I want to break up among multiple lines. What do I use and what is the syntax?
10 Answers
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What exactly are unmanaged resources?
...g Dispose on that object, or (in C#) using the using statement which will handle calling Dispose for you.
If you neglect to Dispose of your unmanaged resources correctly, the garbage collector will eventually handle it for you when the object containing that resource is garbage collected (this is "...
Message Queue vs Message Bus — what are the differences?
And are there any? To me, MB knows both subscribers and publishers and acts as a mediator, notifying subscribers on new messages (effectively a "push" model). MQ, on the other hand, is more of a "pull" model, where consumers pull messages off a queue.
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Checking if a double (or float) is NaN in C++
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According to the IEEE standard, NaN values have the odd property that comparisons involving them are always false. That is, for a float f, f != f will be true only if f is NaN.
Note that, as some comments below have pointed out, not all compilers ...
Getting output of system() calls in Ruby
If I call a command using Kernel#system in Ruby, how do I get its output?
15 Answers
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Saving and loading objects and using pickle
I´m trying to save and load objects using pickle module.
First I declare my objects:
7 Answers
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What is move semantics?
...cott Meyers regarding C++0x . Most of the new features made sense to me, and I am actually excited about C++0x now, with the exception of one. I still don't get move semantics ... What is it exactly?
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