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Java8: Why is it forbidden to define a default method for a method from java.lang.Object
...single Displayable to implement toString() or extend a DisplayableToString base class.
– Brandon
Jun 10 '14 at 22:07
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SQLAlchemy: cascade delete
...ld object from parent.children, should that object be deleted from the database, or should only it's reference to the parent be removed (ie. set parentid column to null, instead of deleting the row)
– Steven
Feb 8 '16 at 13:04
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Update multiple rows in same query using PostgreSQL
...
Based on the solution of @Roman, you can set multiple values:
update users as u set -- postgres FTW
email = u2.email,
first_name = u2.first_name,
last_name = u2.last_name
from (values
(1, 'hollis@weimann.biz', 'Holli...
belongs_to through associations
...
You can also delegate:
class Company < ActiveRecord::Base
has_many :employees
has_many :dogs, :through => :employees
end
class Employee < ActiveRescord::Base
belongs_to :company
has_many :dogs
end
class Dog < ActiveRecord::Base
belongs_to :employee
deleg...
Design Patterns: Abstract Factory vs Factory Method
...oduct. (It is better than the Static Factory. When new types are added the base Product class does not need to be changed only the Simple Factory Class)
Factory Method
Contains one method to produce one type of product related to its type. (It is better than a Simple Factory because the type is ...
Difference between __getattr__ vs __getattribute__
...ve from object, old-style classes are those in Python 2.x with no explicit base class. But the distinction between old-style and new-style classes is not the important one when choosing between __getattr__ and __getattribute__.
You almost certainly want __getattr__.
...
Load dimension value from res/values/dimension.xml from source code
...etrieve a dimensional for a particular resource ID. Unit conversions
are based on the current DisplayMetrics associated with the resources.
so if you want exact dp value just as in xml just divide it with DisplayMetrics density
int dp = (int) (getResources().getDimension(R.dimen.test) / getReso...
Visual Studio Post Build Event - Copy to Relative Directory Location
... contents of the output directory to a different location under the same "base" folder. This parent folder is a relative part and can vary based on Source Control settings.
...
Developing cross platform mobile application [closed]
...e device. The most famous (in fact the only one I know) are commercial and based on the Mono project (C# development):
MonoTouch for iPhone [ 1 ]
MonoDroid for Android (still in development)
Similar project for BlackBerry (still in development)
But I'm not sure we can really call this cross-plat...
Compiling C++11 with g++
...+0x. Here's a quote from the man page:
The compiler can accept several base standards, such as c89 or c++98,
and GNU dialects of those standards, such as gnu89 or gnu++98. By
specifying a base standard, the compiler will accept all programs
following that standard and those using GNU exten...