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Case in Select Statement
...earched CASE expression allows for values to be replaced in the result set based on comparison values. The following example displays the list price as a text comment based on the price range for a product.
USE AdventureWorks2012;
GO
SELECT ProductNumber, Name, "Price Range" =
CASE
...
Paperclip::Errors::MissingRequiredValidatorError with Rails 4
...s_attachment_content_type in Model
Rails 3
class User < ActiveRecord::Base
attr_accessible :avatar
has_attached_file :avatar, :styles => { :medium => "300x300>", :thumb => "100x100>" }, :default_url => "/images/:style/missing.png"
validates_attachment_content_type :avatar, :co...
What are the differences between LinearLayout, RelativeLayout, and AbsoluteLayout?
...n align views one by one (vertically/ horizontally).
RelativeLayout means based on relation of views from its parents and other views.
ConstraintLayout is similar to a RelativeLayout in that it uses relations to position and size widgets, but has additional flexibility and is easier to use in the ...
How to create SBT project with IntelliJ Idea?
...g. Afterwards one can just do File -> New Project -> Scala -> SBT based. IntelliJ will generate basic build.sbt, download necessary dependencies and open project.
SBT Plugin
Sbt plugin that generate an idea project based on the sbt files can be found here: https://github.com/mpeltonen/sb...
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
...
`static` keyword inside function?
... static $cache = null;
if ($cache === null) {
$cache = '%heavy database stuff or something%';
}
// code using $cache
}
In this example, the if would only be executed once. Even if multiple calls to doStuff would occur.
...
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
...
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...
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__.
...