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How to change column datatype in SQL database without losing data
I have SQL Server database and I just realized that I can change the type of one of the columns from int to bool .
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How do I create and read a value from cookie?
How can I create and read a value from a cookie in JavaScript?
19 Answers
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Difference between signed / unsigned char [duplicate]
So I know that the difference between a signed int and unsigned int is that a bit is used to signify if the number if positive or negative, but how does this apply to a char ? How can a character be positive or negative?
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Why does C++ rand() seem to generate only numbers of the same order of magnitude?
In a small application written in C/C++, I am facing a problem with the rand function and maybe the seed :
9 Answers
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Declaration/definition of variables locations in ObjectiveC?
Ever since starting to work on iOS apps and objective C I've been really puzzled by the different locations where one could be declaring and defining variables. On one hand we have the traditional C approach, on the other we have the new ObjectiveC directives that add OO on top of that. Could you fo...
How to check whether a pandas DataFrame is empty?
How to check whether a pandas DataFrame is empty? In my case I want to print some message in terminal if the DataFrame is empty.
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How to map and remove nil values in Ruby
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Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simp...
Finding three elements in an array whose sum is closest to a given number
Given an array of integers, A 1 , A 2 , ..., A n , including negatives and positives, and another integer S. Now we need to find three different integers in the array, whose sum is closest to the given integer S. If there exists more than one solution, any of them is ok.
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Difference between CTE and SubQuery?
...rsions, they are probably very similar. You would have to use the profiler and actual execution plan to spot any differences, and that would be specific to your setup (so we can't tell you the answer in full).
In general; A CTE can be used recursively; a sub-query cannot. This makes them especially...
delete vs delete[] operators in C++
What is the difference between delete and delete[] operators in C++?
7 Answers
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