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Foreign Key naming scheme
I'm just getting started working with foreign keys for the first time and I'm wondering if there's a standard naming scheme to use for them?
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Create a “with” block on several context managers? [duplicate]
Suppose you have three objects you acquire via context manager, for instance A lock, a db connection and an ip socket.
You can acquire them by:
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Is there a bash command which counts files?
Is there a bash command which counts the number of files that match a pattern?
14 Answers
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What is declarative programming? [closed]
I keep hearing this term tossed around in several different contexts. What is it?
18 Answers
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How can I split a comma delimited string into an array in PHP?
I need to split my string input into an array at the commas.
10 Answers
10
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RGB to hex and hex to RGB
How to convert colors in RGB format to hex format and vice versa?
50 Answers
50
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Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
I've been profiling some of our core math on an Intel Core Duo, and while looking at various approaches to square root I've noticed something odd: using the SSE scalar operations, it is faster to take a reciprocal square root and multiply it to get the sqrt, than it is to use the native sqrt opcode!...
Python vs Cpython
What's all this fuss about Python and CPython (Jython,IronPython) , I don't get it:
9 Answers
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Peak signal detection in realtime timeseries data
Update: The best performing algorithm so far is this one .
33 Answers
33
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Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
In multiple courses, books, and jobs, I have seen text fields defined as VARCHAR(255) as kind of the default for "shortish" text. Is there any good reason that a length of 255 is chosen so often, other than being a nice round number ? Is it a holdout from some time in the past when there was a go...