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Get top n records for each group of grouped results
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Here is one way to do this, using UNION ALL (See SQL Fiddle with Demo). This works with two groups, if you have more than two groups, then you would need to specify the group number and add queries for each group:
(
select *
from mytable
where `group` = 1
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How to Load an Assembly to AppDomain with all references recursively?
...e I wrote to solve this problem: github.com/jduv/AppDomainToolkit. Specifically, look at the LoadAssemblyWithReferences method in this class: github.com/jduv/AppDomainToolkit/blob/master/AppDomainToolkit/…
– Jduv
Mar 14 '13 at 14:44
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How to pipe stdout while keeping it on screen ? (and not to a output file)
... /dev/tty | tee -a other.log | grep -i 'foo' >> foo.log to 1) get it all to the console, 2) get it all appended to another file, 3) get the foo lines to a different file.
– Jesse Chisholm
Mar 9 '17 at 16:05
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Vim: What's the difference between let and set?
...iendly interface specialized for options
E.g.
:verbose set
to display all options in effect.
:set tw=40
Will work as a shorthand for set textwidth=40
:set wrap&
Will set the default value for option wrap
:set nowrap
Will unset the option
:set wrap!
Will toggle the option
Most i...
How does the Comma Operator work
...t", "xor";
Notice that due to operator precedence, the code is (intentionally!) identical to
(((keywords = "and"), "or"), "not"), "xor";
That is, the first operator called is keywords.operator =("and") which returns a proxy object on which the remaining operator,s are invoked:
keywords.operato...
Rails Model, View, Controller, and Helper: what goes where?
...summarized) by the Model, or generated from the Controller. If your View really needs to do processing that can't be done by the Model or Controller, put the code in a Helper. Lots of Ruby code in a View makes the pages markup hard to read.
Model: Your model should be where all your code that rela...
How do I know if a generator is empty from the start?
..., there is no simple way. There are a whole lot of work-arounds.
There really shouldn't be a simple way, because of what generators are: a way to output a sequence of values without holding the sequence in memory. So there's no backward traversal.
You could write a has_next function or maybe eve...
Python function overloading
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What you are asking for is called multiple dispatch. See Julia language examples which demonstrates different types of dispatches.
However, before looking at that, we'll first tackle why overloading is not really what you want in python.
Why Not Overl...
Calling method using JavaScript prototype
Is it possible to call the base method from a prototype method in JavaScript if it's been overridden?
14 Answers
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How different is Objective-C from C++? [closed]
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Short list of some of the major differences:
C++ allows multiple inheritance, Objective-C doesn't.
Unlike C++, Objective-C allows method parameters to be named and the method signature includes only the names and types of the parameters and return type (see bbum's and Chuck...