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Parameterize an SQL IN clause
...er 7 and later will auto-parameterize queries, so using parameters isn't really necessary from a performance standpoint - it is, however, critical from a security standpoint - especially with user inputted data like this.
sh...
Fast Linux File Count for a large number of files
...ke a while if there are a lot of them. Also there will be no output until all of the names are read and sorted. Use the ls -f option to turn off sorting.
ls -f | wc -l
Note that this will also enable -a, so ., .., and other files starting with . will be counted.
...
Numpy: find first index of value fast
...ments it. If you use anaconda python distribution it should already be installed.
The code will be compiled so it will be fast.
@jit(nopython=True)
def find_first(item, vec):
"""return the index of the first occurence of item in vec"""
for i in xrange(len(vec)):
if item == vec[i]:
...
What are C++ functors and their uses?
...42); // create an instance of the functor class
int i = add42(8); // and "call" it
assert(i == 50); // and it added 42 to its argument
std::vector<int> in; // assume this contains a bunch of values)
std::vector<int> out(in.size());
// Pass a functor to std::transform, which calls the fu...
Java Keytool error after importing certificate , “keytool error: java.io.FileNotFoundException & Acc
...mmand prompt in administrator mode. If not, you can also go to start -> all programs -> accessories -> right click command prompt and click 'run as administrator'.
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How to make lists contain only distinct element in Python? [duplicate]
...ving
return list(_f(seq, idfun))
def _f(seq, idfun=None):
''' Originally proposed by Andrew Dalke '''
seen = set()
if idfun is None:
for x in seq:
if x not in seen:
seen.add(x)
yield x
else:
for x in seq:
x = idfun(x)
if x not in seen:
s...
What exactly is Java EE?
... Spring to make the developers more easy as to developing among others the service layer.
Only when you're using a bare-bones servlet container such as Tomcat and can't move on to a Java EE server, then Spring is more attractive as it's easier to install Spring on Tomcat. It isn't possible to instal...
What exactly is a Context in Java? [duplicate]
...mming in Java, you have a Request, and a Response. These are passed to the service method of a Servlet.
A property of the Servlet is the ServletConfig, and within that is a ServletContext.
The ServletContext is used to tell the servlet about the Container that the Servlet is within.
So, the Servl...
How to change the background color of the options menu?
...
After spending a considerable amount of time trying all the options, the only way I was able to get an app using AppCompat v7 to change the overflow menu background was using the itemBackground attribute:
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar"&...
How to paste yanked text into the Vim command line
...you know how to use them you cannot live without them.
Registers are basically storage locations for strings. Vim has many registers that work in different ways:
0 (yank register: when you use y in normal mode, without specifying a register, yanked text goes there and also to the default register...