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Interfaces vs. abstract classes [duplicate]
...o functions
Have slightly more control in how the "interface" methods are called
Ability to provide behavior related or unrelated to the interface for "free"
Interfaces are merely data passing contracts and do not have these features. However, they are typically more flexible as a type can only be...
Dependency Injection vs Factory Pattern
...
When using a factory your code is still actually responsible for creating objects. By DI you outsource that responsibility to another class or a framework, which is separate from your code.
sha...
Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
CSS Properties: Display vs. Visibility
... display property tells the browser how to draw and show an element, if at all - whether it should be displayed as an inline element (i.e. it flows with text and other inline elements) or a block-level element (i.e. it has height and width properties that you can set, it's floatable, etc), or an inl...
In git how is fetch different than pull and how is merge different than rebase?
...aving your local* branch unchanged.
pull will perform a fetch and additionally merge the changes into your local branch.
What's the difference? pull updates you local branch with changes from the pulled branch. A fetch does not advance your local branch.
merge vs rebase
Given the following histo...
LINQ-to-SQL vs stored procedures? [closed]
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Some advantages of LINQ over sprocs:
Type safety: I think we all understand this.
Abstraction: This is especially true with LINQ-to-Entities. This abstraction also allows the framework to add additional improvements that you can easily take advantage of. PLINQ is an example of adding...
ASP.NET Web Site or ASP.NET Web Application?
...antly, it will come up with new names for the DLL files generated by pages all the time. That can lead to having several close copies of DLL files containing the same class name,
which will generate plenty of errors. The Web Site project was introduced with Visual Studio 2005, but it has turned o...
Can an Option in a Select tag carry multiple values?
...
I was actually wondering this today, and I achieved it by using the php explode function, like this:
HTML Form (in a file I named 'doublevalue.php':
<form name="car_form" method="post" action="doublevalue_action.php">
...
Where is JAVA_HOME on macOS Mojave (10.14) to Lion (10.7)?
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With the Java optional package or Oracle JDK installed,
adding one of the following lines to your ~/.bash_profile file will set the environment variable accordingly.
export JAVA_HOME="$(/usr/libexec/java_home -v 1.6)"
or
export JAVA_HOME="$(/usr/libexec/java_home -v 1.7)...
Compiled vs. Interpreted Languages
...et machine, but instead read and executed by some other program (which normally is written in the language of the native machine). For example, the same "+" operation would be recognised by the interpreter at run time, which would then call its own "add(a,b)" function with the appropriate arguments,...