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Postgres - FATAL: database files are incompatible with server
...an run the below command to upgrade your postgres data directory retaining all data:
brew postgresql-upgrade-database
The above command is taken from the output of brew info postgres
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impr...
Preserve Line Breaks From TextArea When Writing To MySQL
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Out of all the answers, this one is least concise
– JacobRossDev
Aug 14 '15 at 21:04
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How do I print a double value with full precision using cout?
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Is the really the right answer? When I manually use a high number, I can print out as many as 51 digits of approximated e, but with cout.precision(numeric_limits<double>::digits10 + 2); I only get 16....
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Postgresql aggregate array
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Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need ...
What is the performance of Objects/Arrays in JavaScript? (specifically for Google V8)
Performance associated with Arrays and Objects in JavaScript (especially Google V8) would be very interesting to document. I find no comprehensive article on this topic anywhere on the Internet.
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Removing packages installed with go get
... I needed to set my GOPATH otherwise that package sullies my root Go install (I would much prefer to keep my Go install clean and separate core from custom). How do I remove packages installed previously?
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Alphabet range in Python
...gt;>> string.ascii_lowercase
'abcdefghijklmnopqrstuvwxyz'
If you really need a list:
>>> list(string.ascii_lowercase)
['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
And to do it with range
>&g...
Error handling in Bash
...kens code's predictability and portability).
You can either let the trap call error for you (in which case it uses the default exit code of 1 and no message) or call it yourself and provide explicit values; for instance:
error ${LINENO} "the foobar failed" 2
will exit with status 2, and give an ...
getSupportActionBar from inside of Fragment ActionBarCompat
...ctivity().
You'll need to cast it to an ActionBarActivity then make the call to getSupportActionBar().
((AppCompatActivity)getActivity()).getSupportActionBar().setSubtitle(R.string.subtitle);
You do need the cast. It's not poor design, it's backwards compatibility.
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What is a “context bound” in Scala?
... Iterable[T]) =
xs zip ys map { t => implicitly[Numeric[T]].times(t._1, t._2) }
or
def **[T : Numeric](xs: Iterable[T], ys: Iterable[T]) =
xs zip ys map { t => context[T]().times(t._1, t._2) }
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