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How to get values from IGrouping
...> implements IEnumerable<TElement>, you can use SelectMany to put all the IEnumerables back into one IEnumerable all together:
List<smth> list = new List<smth>();
IEnumerable<IGrouping<int, smth>> groups = list.GroupBy(x => x.id);
IEnumerable<smth> smths = ...
Create zip file and ignore directory structure
... sometime it just doesn't work... prefer @czerasz link ;) which basically is a pushd popd combo
– TecHunter
Oct 28 '16 at 8:33
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SQL JOIN - WHERE clause vs. ON clause
...der and its lines, if any, for order number 12345. The second will return all orders, but only order 12345 will have any lines associated with it.
With an INNER JOIN, the clauses are effectively equivalent. However, just because they are functionally the same, in that they produce the same results...
Remove IE10's “clear field” X button on certain inputs?
...u should never use Compatibility Mode in an actual website. It’s not actually compatible :)
– Ry-♦
Aug 11 '13 at 14:19
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How important is the order of columns in indexes?
... 3, the optimizer wouldn't even use the index, because it's not helpful at all in narrowing down the result sets. Anytime you're in a query, narrowing down the number of results to deal with before the next step means better performance.
Since the index is also stored this way, there's no backtrac...
“int main (vooid)”? How does that work?
I recently had to type in a small C test program and, in the process, I made a spelling mistake in the main function by accidentally using vooid instead of void .
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How to get div height to auto-adjust to background size?
How do I get a div to automatically adjust to the size of the background I set for it without setting a specific height (or min-height) for it?
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Setting the Vim background colors
... Thanks, it works. I tried that option before, but it seems that not all colors work, for instance brown and yellow options don't affect my default console background at all.
– Maksim Vi.
Jul 13 '09 at 2:52
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Just what is Java EE really? [closed]
...the libraries function outside of the application server environment?
Actually they can. Most of the libraries can be directly used standalone (in Java SE) or included in a .war (practically that's nearly always Tomcat). Some parts of Java EE, like JPA, have explicit sections in their respective sp...
Better explanation of when to use Imports/Depends
...n, however, be thwarted if another package, loaded later, places an identically named function earlier on the search path. Chambers (in SoDA) uses the example of the function "gam", which is found in both the gam and mgcv packages. If two other packages were loaded, one of them depending on gam and...