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Using LIMIT within GROUP BY to get N results per group?
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You could use GROUP_CONCAT aggregated function to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
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Using R to download zipped data file, extract, and import data
...ZGraphs on Twitter writes:
"Lots of online csvs are zipped. Is there a way to download, unzip the archive, and load the data to a data.frame using R? #Rstats"
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What's the strangest corner case you've seen in C# or .NET? [closed]
I collect a few corner cases and brain teasers and would always like to hear more. The page only really covers C# language bits and bobs, but I also find core .NET things interesting too. For example, here's one which isn't on the page, but which I find incredible:
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Logical operators (“and”, “or”) in DOS batch
How would you implement logical operators in DOS Batch files?
12 Answers
12
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Is it possible to view RabbitMQ message contents directly from the command line?
Is it possible to view RabbitMQ message contents directly from the command line?
6 Answers
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Where in a virtualenv does the custom code go?
What sort of directory structure should one follow when using virtualenv ? For instance, if I were building a WSGI application and created a virtualenv called foobar I would start with a directory structure like:
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Which C++ idioms are deprecated in C++11?
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Final Class: C++11 provides the final specifier to prevent class derivation
C++11 lambdas substantially reduce the need for named function object (functor) classes.
Move Constructor: The magical ways in which std::auto_ptr works are no longer needed due to first-class supp...
How do you append an int to a string in C++? [duplicate]
I'd like it to print Player 4 .
20 Answers
20
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When to use std::begin and std::end instead of container specific versions [duplicate]
... look at, say, the definition of std::begin:
template< class C >
auto begin( C& c ) -> decltype(c.begin());
You see that all it does is reference the begin() anyway. I suppose a decent compiler will make the difference nil, so I guess it comes down to preference. Personally, I'd u...
Bash script to set up a temporary SSH tunnel
On Cygwin, I want a Bash script to:
6 Answers
6
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