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Difference between a theta join, equijoin and natural join
I'm having trouble understanding relational algebra when it comes to theta joins, equijoins and natural joins. Could someone please help me better understand it? If I use the = sign on a theta join is it exactly the same as just using a natural join?
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How to tell if a string is not defined in a Bash shell script
...Autoconf, you'll find that they do not recommend combining terms with '-a' and do recommend using separate simple tests combined with &&. I've not encountered a system where there is a problem; that doesn't mean they didn't used to exist (but they are probably extremely rare these days, eve...
Asking the user for input until they give a valid response
...put the input method in a while loop. Use continue when you get bad input, and break out of the loop when you're satisfied.
When Your Input Might Raise an Exception
Use try and except to detect when the user enters data that can't be parsed.
while True:
try:
# Note: Python 2.x users s...
Studies on optimal code width?
...racters. I tend to change it to 120 for no reason other than it was the standard at a company I was with a few years back, and no other company has told me to do it differently.
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Is there a library function for Root mean square error (RMSE) in python?
...lso known as MSE, RMD, or RMS. What problem does it solve?
If you understand RMSE: (Root mean squared error), MSE: (Mean Squared Error) RMD (Root mean squared deviation) and RMS: (Root Mean Squared), then asking for a library to calculate this for you is unnecessary over-engineering. All these me...
Android Studio doesn't see device
The AVD Manager in Android Studio doesn't show my device but adb devices does show it. Am I missing something obvious here?
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When should I use the Visitor Design Pattern? [closed]
...dmit, I just don't get it. I read the wikipedia article for the pattern and I understand its mechanics but I'm still confused as to when I'd use it.
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twitter-bootstrap vs jquery-mobile [closed]
...will only show a single div with data-role='page' at a time), AJAX preload and history API, and lots of touch friendly components/widgets. Whereas bootstrap is foremost a CSS library mostly for desktop but works on mobile as well especially since 2.0 comes with media queries built in. Bootstrap wi...
Is there a good Valgrind substitute for Windows?
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Insure++ takes forever to instrument your code, and forever to execute your code at runtime.
– C Johnson
Aug 9 '10 at 15:12
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So, JSONP or CORS? [closed]
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This is a pretty broad question, and could warrant a wiki unto itself. There is also quite a bit on google regarding the two, but I think I can hit a few key points.
If you need a read-only ajax interface to your servers and you need to support IE<=9...