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select * vs select column
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It always pulls a tuple (except in cases where the table has been vertically segmented - broken up into columns pieces), so, to answer the question you asked, it doesn't matter from a performance perspective. However, for ma...
When should TaskCompletionSource be used?
AFAIK, all it knows is that at some point, its SetResult or SetException method is being called to complete the Task<T> exposed through its Task property.
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How to sort a dataframe by multiple column(s)
I want to sort a data.frame by multiple columns. For example, with the data.frame below I would like to sort by column z (descending) then by column b (ascending):
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Python unittest - opposite of assertRaises?
I want to write a test to establish that an Exception is not raised in a given circumstance.
10 Answers
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ReactJS - Does render get called any time “setState” is called?
...te(object nextProps, object nextState), each component has this method and it's responsible to determine "should component update (run render function)?" every time you change state or pass new props from parent component.
You can write your own implementation of shouldComponentUpdate method for yo...
How is the fork/join framework better than a thread pool?
What are the benefits of using the new fork/join framework over just simply splitting the big task into N subtasks in the beginning, sending them to a cached thread pool (from Executors ) and waiting for each task to complete? I fail to see how using the fork/join abstraction simplifies the prob...
Unique (non-repeating) random numbers in O(1)?
...t doesn't resort to something like an O(N) search of previous values to do it. Is this possible?
22 Answers
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Why are preprocessor macros evil and what are the alternatives?
...ved a really good answer; I think that almost any programmer before even writing the first "Hello World" had encountered a phrase like "macro should never be used", "macro are evil" and so on, my question is: why? With the new C++11 is there a real alternative after so many years?
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How does a “stack overflow” occur and how do you prevent it?
How does a stack overflow occur and what are the best ways to make sure it doesn't happen, or ways to prevent one, particularly on web servers, but other examples would be interesting as well?
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public friend swap member function
...ful answer to the copy-and-swap-idiom there is a piece of code I need a bit of help:
2 Answers
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