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Is an index needed for a primary key in SQLite?
When an integer column is marked as a primary key in an SQLite table, should an index be explicitly created for it as well? SQLite does not appear to automatically create an index for a primary key column, but perhaps it indexes it anyway, given its purpose? (I will be searching on that column all t...
What is meant by Ems? (Android TextView)
What is meant by Ems (related to a TextView)? For example in
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Correct way to use get_or_create?
I'm trying to use get_or_create for some fields in my forms, but I'm getting a 500 error when I try to do so.
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What's the valid way to include an image with no src?
I have an image that I will dynamically populate with a src later with javascript but for ease I want the image tag to exist at pageload but just not display anything. I know <img src='' /> is invalid so what's the best way to do this?
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How to make an immutable object in Python?
Although I have never needed this, it just struck me that making an immutable object in Python could be slightly tricky. You can't just override __setattr__ , because then you can't even set attributes in the __init__ . Subclassing a tuple is a trick that works:
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Capture key press (or keydown) event on DIV element
How do you trap the keypress or key down event on a DIV element (using jQuery)?
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How is set() implemented?
I've seen people say that set objects in python have O(1) membership-checking. How are they implemented internally to allow this? What sort of data structure does it use? What other implications does that implementation have?
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Sprintf equivalent in Java
Printf got added to Java with the 1.5 release but I can't seem to find how to send the output to a string rather than a file (which is what sprintf does in C). Does anyone know how to do this?
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Windows: How to specify multiline command on command prompt?
how do we extend a command to next line?
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How to get the current directory in a C program?
I'm making a C program where I need to get the directory that the program is started from. This program is written for UNIX computers. I've been looking at opendir() and telldir() , but telldir() returns a off_t (long int) , so it really doesn't help me.
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