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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...
What are the underlying data structures used for Redis?
I'm trying to answer two questions in a definitive list:
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How to make a flat list out of list of lists?
I wonder whether there is a shortcut to make a simple list out of list of lists in Python.
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Printing a variable memory address in swift
Is there anyway to simulate the [NSString stringWithFormat:@"%p", myVar] , from Objective-C, in the new Swift language?
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Unix's 'ls' sort by name
Can you sort an ls listing by name?
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is it possible to select EXISTS directly as a bit?
I was wondering if it's possible to do something like this (which doesn't work):
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Preferred method to store PHP arrays (json_encode vs serialize)
I need to store a multi-dimensional associative array of data in a flat file for caching purposes. I might occasionally come across the need to convert it to JSON for use in my web app but the vast majority of the time I will be using the array directly in PHP.
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How do I append one string to another in Python?
I want an efficient way to append one string to another in Python, other than the following.
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How to get line count of a large file cheaply in Python?
I need to get a line count of a large file (hundreds of thousands of lines) in python. What is the most efficient way both memory- and time-wise?
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Rename a dictionary key
Is there a way to rename a dictionary key, without reassigning its value to a new name and removing the old name key; and without iterating through dict key/value?
In case of OrderedDict, do the same, while keeping that key's position.
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