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How do I (or can I) SELECT DISTINCT on multiple columns?
...would qualify as "distinct" (though looking identical to the human eye):
(123, NULL)
(123, NULL)
Also passes in a unique index and almost anywhere else, since NULL values do not compare equal according to the SQL standard. See:
Create unique constraint with null columns
OTOH, GROUP BY, DISTIN...
How to bundle a native library and a JNI library inside a JAR?
...
It is possible to create a single JAR file with all dependencies including the native JNI libraries for one or more platforms. The basic mechanism is to use System.load(File) to load the library instead of the typical System.loadLib...
Running python script inside ipython
Is it possible to run a python script (not module) from inside ipython without indicating its path? I tried to set PYTHONPATH but it seems to work only for modules.
I would like to execute
...
Apache Prefork vs Worker MPM
...ne and only one MPM must be loaded into the server at any time. MPMs are chosen during configuration and compiled into the server by using the argument --with-mpm=NAME with the configure script where NAME is the name of the desired MPM.
Apache will use a default MPM for each operating system unless...
Why doesn't C# support the return of references?
...rn ref x;
else
return ref y;
}
and then call it with
int a = 123;
int b = 456;
ref int c = ref Max(ref a, ref b);
c += 100;
Console.WriteLine(b); // 556!
I know empirically that it is possible to build a version of C# that supports these features because I have done so. Advanced pr...
ImportError: No module named pip
OS: Mac OS X 10.7.5
Python Ver: 2.7.5
16 Answers
16
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Best way to make Django's login_required the default
...ication, this model will work. If this isn't a one-to-one fit, you may choose to modify the middleware to suit your circumstances more closely.
What I like about this approach - besides removing the necessity of littering the codebase with @login_required decorators - is that if the authentication...
How do I access my SSH public key?
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on Mac OS X: cat ~/.ssh/id_rsa.pub
– karlingen
Apr 9 '14 at 8:40
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Download the Android SDK components for offline install
Is it possible to download the Android SDK components for offline install without using the SDK Manager?
The problem is I am behind a firewall which I have no control over and both sites download URLs seem to be blocked (throws a connection refused exception)
...
Are there any smart cases of runtime code modification?
...ardware Software Tradeoffs for Bitmap Graphics on the Blit (1984) or this posting (2006) by Chris Lattner on Apple's use of LLVM for runtime code specialization in their OpenGL stack.
In some cases software resorts to a technique known as trampoline which involves the dynamic creation of code on the...