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Which kind of pointer do I use when?
...ovariant returns, non-owning pointing which can happen. They're not terrifically useful otherwise.
Array pointers: unique_ptr has a specialization for T[] which automatically calls delete[] on the result, so you can safely do unique_ptr<int[]> p(new int[42]); for example. shared_ptr you'd sti...
What is the purpose of setting a key in data.table?
...creasing order.
marks those columns as key columns by setting an attribute called sorted to DT.
The reordering is both fast (due to data.table's internal radix sorting) and memory efficient (only one extra column of type double is allocated).
When is setkey() required?
For grouping operations, s...
I want my android application to be only run in portrait mode?
...Coelho you can actually make a base class PortraitActivity and in onCreate call setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT) All activities extending this won't rotate
– Twinone
Jun 6 '14 at 9:07
...
How can Bash execute a command in a different directory context?
I have a common command that gets called from within very specific directories. There is only one executable sitting in /bin for this program, and the current working directory is very important for running it correctly. The script affects the files that live inside the directory it is run within.
...
Difference between fmt.Println() and println() in Go
...n -gcflags="-m" test.go
# command-line-arguments
./test.go:12:12: inlining call to fmt.Printf
./test.go:6:10: new(struct {}) does not escape
./test.go:7:10: new(struct {}) does not escape
./test.go:10:10: new(struct {}) escapes to heap
./test.go:11:10: new(struct {}) escapes to heap
./test.go:12:35:...
Capturing URL parameters in request.GET
...ts.get(username=username)
message = request.GET.get('message')
As a side note, you'll find the request method (in this case "GET", and for submitted forms usually "POST") in request.method. In some cases it's useful to check that it matches what you're expecting.
Update: When deciding whether...
Flask-SQLalchemy update a row's information
... you're still confused on the differences after reading through there, consider asking another question.
– Mark Hildreth
Jul 15 '11 at 15:36
...
What's the difference between getRequestURI and getPathInfo methods in HttpServletRequest?
... is deployed under /app.
http://30thh.loc:8480/app/test%3F/a%3F+b;jsessionid=S%3F+ID?p+1=c+d&p+2=e+f#a
Method URL-Decoded Result
----------------------------------------------------
getContextPath() no /app
getLocalAddr() 127.0.0.1
getLocalN...
Rails server says port already used, how to kill that process?
...s what webrick normally uses), type this in your terminal to find out the PID of the process:
$ lsof -wni tcp:3000
Then, use the number in the PID column to kill the process:
$ kill -9 PID
share
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How to use OrderBy with findAll in Spring Data
...Entity, Integer> {
public List<StudentEntity> findAllByOrderByIdAsc();
}
The code above should work. I'm using something similar:
public List<Pilot> findTop10ByOrderByLevelDesc();
It returns 10 rows with the highest level.
IMPORTANT:
Since I've been told that it's easy to mi...