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Django ManyToMany filter()
...d it.
the above code will end up generating SQL that looks something like:
SELECT * FROM users WHERE id IN (SELECT user_id FROM userzones WHERE zone_id IN (1,2,3))
which is nice because it doesn't have any intermediate joins that could cause duplicate users to be returned
...
How does comparison operator works with null int?
...e("num1 is greater than or equal to num2");
}
else
{
// This clause is selected, but num1 is not less than num2.
Console.WriteLine("num1 >= num2 returned false (but num1 < num2 also is false)");
}
if (num1 < num2)
{
Console.WriteLine("num1 is less than num2");
}
else
{
// T...
SSH Private Key Permissions using Git GUI or ssh-keygen are too open
..., not Cygwin):
In the windows explorer, right-click your id_rsa file and select Properties
Select the Security tab and click Edit...
Check the Deny box next to Full Control for all groups EXCEPT Administrators
Retry your Git command
...
Sort a list from another list IDs
...; source,
IEnumerable<TId> order,
Func<T, TId> idSelector)
{
var lookup = source.ToDictionary(idSelector, t => t);
foreach (var id in order)
{
yield return lookup[id];
}
}
Is a generic extension for what you want.
You could use the extension li...
How to create a date and time picker in Android? [closed]
.... This Date object contains
// the date and time that the user has selected.
}
@Override
public void onDateTimeCancel()
{
// Overriding onDateTimeCancel() is optional.
}
};
Then you create and show the dialog:
new SlideDateTimePicker.Builder(getSupportFragment...
Really Cheap Command-Line Option Parsing in Ruby
...y chairs are in the classroom", :default => 1
p.option :room_number, "select room number", :default => 2, :value_in_set => [1,2,3,4]
end.process!
Calling the script with -h or --help will print
Usage: micro-optparse-example [options]
-v, --[no-]verbose turn on verbose...
When should std::move be used on a function return value? [duplicate]
...e object to be copied is designated by an lvalue, overload
resolution to select the constructor for the copy is first performed as
if the object were designated by an rvalue.
return foo; is a case of NRVO, so copy elision is permitted. foo is an lvalue. So the constructor selected for the "co...
What's the difference between session.persist() and session.save() in Hibernate?
...st(entity);
session.getTransaction().commit();
session.close();
Result:
select nextval ('hibernate_sequence') // This is for vehicle Id generated : 36
insert into Employee_Vehicle ( Vehicle_Name, Vehicle_Id) values ( Honda, 36)
Note the result is same when you get an already persisted object an...
When should you use 'friend' in C++?
...te, the C++ FAQ mentions that friend enhances encapsulation. friend grants selective access to members, just like protected does. Any fine-grained control is better than granting public access. Other languages define selective access mechanisms too, consider C#'s internal. Most negative criticism ar...
Can't execute jar- file: “no main manifest attribute”
...o specify the Application's entry point in eclipse.
When you say Export,
Select Jar and next
[ give it a name in the next window ] and next
and next again
and you'll see " Select the class of the application entry point".
Just pick a class and Eclipse will automatically build a cool MANIFEST....