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MySQL: multiple tables or one table with many columns?
...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 I wouldn't worry ab...
what is reverse() in Django
...ead django code sometimes, I see in some templates reverse() . I am not quite sure what this is but it is used together with HttpResponseRedirect. How and when is this reverse() supposed to be used?
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Can you Run Xcode in Linux?
Can you run Xcode in Linux? Mac OS X was based on BSD Unix, so is it possible?
13 Answers
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Ubuntu rails install fails on zlib
I've just moved over to Ubuntu 8.10 as my dev box; it's my first serious foray into Linux as a daily-use OS, and I'm having a hard time getting Rails going. I have followed a number of tutorials which all seem to work fine, but when I try and use gem install or gem update on anything, I get an erro...
What exactly are iterator, iterable, and iteration?
What is the most basic definition of "iterable", "iterator" and "iteration" in Python?
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PHP json_decode() returns NULL with valid JSON?
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It could be the encoding of the special characters. You could ask json_last_error() to get definite information.
Update: The issue is solved, look at the "Solution" paragraph in the question.
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Is the sizeof(some pointer) always equal to four?
...int *) == sizeof(double *).
In practice, pointers will be size 2 on a 16-bit system (if you can find one), 4 on a 32-bit system, and 8 on a 64-bit system, but there's nothing to be gained in relying on a given size.
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Change private static final field using Java reflection
I have a class with a private static final field that, unfortunately, I need to change it at run-time.
11 Answers
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Developing GUIs in Python: Tkinter vs PyQt [closed]
...erious, especially as things you learn will translate directly to working with Qt in other languages too if you ever need to, and Qt is probably the best cross-platform interface toolkit available right now.
There are only two real (potential) disadvantages:
PyQt is only available under the GPL. ...
Static Block in Java [duplicate]
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It's a static initializer. It's executed when the class is loaded (or initialized, to be precise, but you usually don't notice the difference).
It can be thought of as a "class constructor".
Note that there are also instanc...