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How to query as GROUP BY in django?
...Another solution is to use the group_by property:
query = Members.objects.all().query
query.group_by = ['designation']
results = QuerySet(query=query, model=Members)
You can now iterate over the results variable to retrieve your results. Note that group_by is not documented and may be changed in ...
When is a CDATA section necessary within a script tag?
...l work fine in both HTML and XHTML. You can easily achieve this by putting all significant code in external scripts and just using inline scripts to eg. initialise variables (escaping &/< to \x26/\x3C in string literals if you need).
– bobince
Sep 20 '09...
Boolean vs boolean in Java
...
It should be noted the a Boolean actually has 3 states... true, false and null where a boolean has the logical 2 states (true and false)
– respectTheCode
Jun 6 '14 at 15:46
...
Designing function f(f(n)) == -n
...turn n - 1
else:
return -1 * (n + 1)
Python automatically promotes integers to arbitrary length longs. In other languages the largest positive integer will overflow, so it will work for all integers except that one.
To make it work for real numbers you need to replace the n ...
Java Multiple Inheritance
...
@MoritzPetersen If you really want to go into reusing abstractions and giving meaningful names, probably AbstractEquidae would be more suitable than AbstractHorse. It would be strange to have a zebra extend an abstract horse. Nice answer, by the way....
How to timeout a thread
... SSCCE:
package com.stackoverflow.q2275443;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
public clas...
How to add Options Menu to Fragment in Android
...
Call the super method:
Java:
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
@Override
public void onCreateOptio...
How do I pass an object from one activity to another on Android? [duplicate]
...tom classes across activities. I have found this very useful.
Here is a small snippet of code I am using
CustomListing currentListing = new CustomListing();
Intent i = new Intent();
Bundle b = new Bundle();
b.putParcelable(Constants.CUSTOM_LISTING, currentListing);
i.putExtras(b);
i.setClass(this,...
What does the exclamation mark do before the function?
...s just a function declaration. You would need an invocation, foo(), to actually run the function.
Now, when we add the seemingly innocuous exclamation mark: !function foo() {} it turns it into an expression. It is now a function expression.
The ! alone doesn't invoke the function, of course, but w...
How to create a dialog with “yes” and “no” options?
...note: you can put a return inside the else and then you don't need to wrap all of your code in the confirm! (case by case fix though)
– Jacob Raccuia
Sep 2 '14 at 14:54
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