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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 define optional methods in Swift protocol?
...an take advantage of powerful generics system.
You can always be sure that all requirements are met when encountering types that conform to such protocol. It's always either concrete implementation or default one. This is how "interfaces" or "contracts" behave in other languages.
Disadvantages
F...
Is ASCII code 7-bit or 8-bit?
...ans it can be fit into 7-bits. So can't it be argued that ASCII bit is actually 7-bit code?
6 Answers
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How do I get the full url of the page I am on in C#
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I usually use Request.Url.ToString() to get the full url (including querystring), no concatenation required.
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Stop jQuery .load response from being cached
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All this cache: false does is append a number (I believe its a timestamp) to the end of a url when making the request. The other place to handle the cache settings are from the server or web app by setting various HTTP respo...
What to put in a python module docstring? [closed]
...ngs; the module's own docstring should describe them very summarily (if at all) and rather concentrate on a concise summary of what the module as a whole can do for you, ideally with some doctested examples (just like functions and classes ideally should have doctested examples in their docstrings)....
How to tell git to ignore individual lines, i.e. gitignore for specific lines of code [duplicate]
...o be filtered:
*.rb filter=gitignore, i.e. run filter named gitignore on all *.rb files
Define the gitignore filter in your gitconfig:
$ git config --global filter.gitignore.clean "sed '/#gitignore$/d'", i.e. delete these lines
$ git config --global filter.gitignore.smudge cat, i.e. do nothing ...
Python non-greedy regexes
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You seek the all-powerful *?
From the docs, Greedy versus Non-Greedy
the non-greedy qualifiers *?, +?, ??, or {m,n}? [...] match as little
text as possible.
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Pointers vs. values in parameters and return values
... function values, and interface values are implemented with pointers internally, and a pointer to them is often redundant.
Elsewhere, use pointers for big structs or structs you'll have to change, and otherwise pass values, because getting things changed by surprise via a pointer is confusing.
O...
Batch script: how to check for admin rights
...went searching for other commands that require elevated permissions. rationallyparanoid.com had a list of a few, so I ran each command on the two opposite extremes of current Windows OSs (XP and 8) in the hopes of finding a command that would be denied access on both OSs when run with standard permi...