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LINQ - Left Join, Group By, and Count
...ns groupings like new{parent,IEnumerable<child>} so you just need to call Count() on the group:
from p in context.ParentTable
join c in context.ChildTable on p.ParentId equals c.ChildParentId into g
select new { ParentId = p.Id, Count = g.Count() }
In Extension Method syntax a join into is ...
C# Thread safe fast(est) counter
...ment locks the bus to prevent another CPU from accessing the bus while the calling CPU does its operation. Now, take a look at the C# lock() statement's IL. Here you will see calls to Monitor in order to begin or end a section.
In other words, .Net lock() statement is doing a lot more than the .N...
Given the lat/long coordinates, how can we find out the city/country?
...asily does thousands of lookups per second)
Disadvantages:
Not automatically up to date
Requires extra code if you want to distinguish the case where the nearest city is dozens of miles away
May give weird results near the poles and the international date line (though there aren't any cities in ...
python list by value not by reference [duplicate]
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Test case for extend() call is not comparable to others. To use extend() you must create an array first while other constructs will create an array for you. So you effectively giving extend() an advantage by skipping initialization of the list obj...
ExpressJS How to structure an application?
...he code
This is just an instance of "group by coupling", but I wanted to call it out specifically. I've written many projects where the tests live under a parallel filesystem called "tests" and now that I've started putting my tests in the same directory as their corresponding code, I'm never goin...
What is Ember RunLoop and how does it work?
...e Ember Run Loop implementation has been split off into a separate library called backburner.js, with some very minor API differences.
First off, read these:
http://blog.sproutcore.com/the-run-loop-part-1/
http://blog.sproutcore.com/the-run-loop-part-2/
They're not 100% accurate to Ember, but th...
Why return NotImplemented instead of raising NotImplementedError
Python has a singleton called NotImplemented .
4 Answers
4
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When using the Java debugger in Intellij what does “Drop Frame” mean?
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The call stack of your application can be viewed in the debugger. Using the "Drop Frame" functionality you can "fall back" to a previous stack frame, in a sense going back in time. This can be helpful to re-enter a function if yo...
What do the different readystates in XMLHttpRequest mean, and how can I use them?
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I'm not sure, @vishalsharma -- as I recall, the readystate is 0 as long as the request is not initialized. After that, any other "completion" (either by success or error) will update the readystate to 4. So losing internet after the transfer starts will flip it t...
Best way to detect Mac OS X or Windows computers with JavaScript or jQuery
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@EternalDarknessThat's why I called it isPC (and not isWindows or isLinux) because Linux runs on PCs but macOS only runs on Macs.
– Benny Neugebauer
Jan 10 '19 at 15:25
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