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must appear in the GROUP BY clause or be used in an aggregate function
... this issue, you must calculate the aggregate in a sub-query and then join it with itself to get the additional columns you'd need to show:
SELECT m.cname, m.wmname, t.mx
FROM (
SELECT cname, MAX(avg) AS mx
FROM makerar
GROUP BY cname
) t JOIN makerar m ON m.cname = t.cname AND t.mx...
Reset Entity-Framework Migrations
I've mucked up my migrations, I used IgnoreChanges on the initial migration, but now I want to delete all my migrations and start with an initial migration with all of the logic.
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Why does auto a=1; compile in C?
...ause local scope is the default for a variable declared inside a function, it's also the same as int a in this example.
This keyword is actually a leftover from C's predecessor B, where there were no base types: everything was int, pointer to int, array of int.(*) Declarations would be either auto ...
Understanding NSRunLoop
...or what is NSRunLoop ? so as I know NSRunLoop is a something connected with NSThread right? So assume I create a Thread like
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What does the “map” method do in Ruby?
... |n| n * n } #=> [1, 4, 9]
Array and Range are enumerable types. map with a block returns an Array. map! mutates the original array.
Where is this helpful, and what is the difference between map! and each? Here is an example:
names = ['danil', 'edmund']
# here we map one array to another, c...
How to disable anchor “jump” when loading a page?
...sh) {
setTimeout(function() {
window.scrollTo(0, 0);
}, 1);
}
Edit: tested and works in Firefox, IE & Chrome on Windows.
Edit 2: move setTimeout() inside if block, props @vsync.
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Creating an empty list in Python
...
Here is how you can test which piece of code is faster:
% python -mtimeit "l=[]"
10000000 loops, best of 3: 0.0711 usec per loop
% python -mtimeit "l=list()"
1000000 loops, best of 3: 0.297 usec per loop
However, in practice, this initialization is most likely an extremely small part of you...
How to run Django's test database only in memory?
My Django unit tests take a long time to run, so I'm looking for ways to speed that up. I'm considering installing an SSD , but I know that has its downsides too. Of course, there are things I could do with my code, but I'm looking for a structural fix. Even running a single test is slow since the ...
How do you beta test an iphone app?
How can you beta test an iPhone app? I can get it on my own device, and anyone that gives me a device, I can run it on theirs, but is there a way to do a limited release via the app store for beta testing?
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Use of Finalize/Dispose method in C#
...doesn't use unmanaged resources, you simply implement a Dispose method as with normal interface implementations:
public sealed class A : IDisposable
{
public void Dispose()
{
// get rid of managed resources, call Dispose on member variables...
}
}
When implementing an unsealed...