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How to DROP multiple columns with a single ALTER TABLE statement in SQL Server?
...ike to write a single SQL command to drop multiple columns from a single table in one ALTER TABLE statement.
11 Answers
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What does the “map” method do in Ruby?
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The map method takes an enumerable object and a block, and runs the block for each element, outputting each returned value from the block (the original object is unchanged unless you use map!):
[1, 2, 3].map { |n| n * n } #=> [1, 4, 9]
Array and Rang...
Python memoising/deferred lookup property decorator
Recently I've gone through an existing code base containing many classes where instance attributes reflect values stored in a database. I've refactored a lot of these attributes to have their database lookups be deferred, ie. not be initialised in the constructor but only upon first read. These attr...
Get selected subcommand with argparse
When I use subcommands with python argparse, I can get the selected arguments.
2 Answers
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How do I associate a Vagrant project directory with an existing VirtualBox VM?
Somehow my Vagrant project has disassociated itself from its VirtualBox VM, so that when I vagrant up Vagrant will import the base-box and create a new virtual machine.
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How to normalize a NumPy array to within a certain range?
After doing some processing on an audio or image array, it needs to be normalized within a range before it can be written back to a file. This can be done like so:
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How to check that a string is a palindrome using regular expressions?
That was an interview question that I was unable to answer:
32 Answers
32
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Lambda capture as const reference?
Is it possible to capture by const reference in a lambda expression?
8 Answers
8
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How do I initialize an empty array in C#?
Is it possible to create an empty array without specifying the size?
13 Answers
13
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How to convert a byte array to a hex string in Java?
I have a byte array filled with hex numbers and printing it the easy way is pretty pointless because there are many unprintable elements. What I need is the exact hexcode in the form of: 3a5f771c
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