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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...
Difference between timestamps with/without time zone in PostgreSQL
... timestamp values stored differently in PostgreSQL when the data type is WITH TIME ZONE versus WITHOUT TIME ZONE ? Can the differences be illustrated with simple test cases?
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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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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 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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Intel HAXM installation error - This computer does not support Intel Virtualization Technology (VT-x
I have an issue with my HAXM installation. Here is the thing. I got this error every single time I tried to install HAXM for my computer:
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SFTP Libraries for .NET [closed]
...ost up to date and best maintained libraries for SFTP (not to be confused with FTPS) communication in .NET. SSH.NET is a clean .NET 4.0 implementation of the SFTP protocol, and I've used it in a couple of solutions with flying colors and great success.
The original SharpSsh seems to be dead and mos...
Why Response.Redirect causes System.Threading.ThreadAbortException?
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The correct pattern is to call the Redirect overload with endResponse=false and make a call to tell the IIS pipeline that it should advance directly to the EndRequest stage once you return control:
Response.Redirect(url, false);
Context.ApplicationInstance.CompleteRequest();
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Show a Form without stealing focus?
I'm using a Form to show notifications (it appears at the bottom right of the screen), but when I show this form it steals the focus from the main Form. Is there a way to show this "notification" form without stealing focus?
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Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...antage of nonblocking or asynchronous I/O is that your thread can continue its work in parallel. Of course you can achieve this also using an additional thread. As you stated for best overall (system) performance I guess it would be better to use asynchronous I/O and not multiple threads (so reducin...