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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
...ld instances (at least,
not at the moment). If a base class has a field called author, you
cannot create another model field called author in any class that
inherits from that base class.
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Create empty queryset by default in django form fields
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432
You can have an empty queryset by doing this:
MyModel.objects.none()
Although i don't know h...
How do I convert a String object into a Hash object?
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The string created by calling Hash#inspect can be turned back into a hash by calling eval on it. However, this requires the same to be true of all of the objects in the hash.
If I start with the hash {:a => Object.new}, then its string represen...
What is the difference between shallow copy, deepcopy and normal assignment operation?
...ble towards the existing object. The docs explain the difference between shallow and deep copies:
The difference between shallow and deep copying is only relevant for
compound objects (objects that contain other objects, like lists or
class instances):
A shallow copy constructs a new...
PHP_SELF vs PATH_INFO vs SCRIPT_NAME vs REQUEST_URI
I am building a PHP application in CodeIgniter. CodeIgniter sends all requests to the main controller: index.php . However, I don't like to see index.php in the URI. For example, http://www.example.com/faq/whatever will route to http://www.example.com/index.php/faq/whatever . I need a reliable...
Why do I get AttributeError: 'NoneType' object has no attribute 'something'?
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answered Apr 10 '17 at 5:32
PHINCY L PIOUSPHINCY L PIOUS
30733 silver badges66 bronze badges
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Java LinkedHashMap get first or last entry
... entry is possible, but will entail iterating over the whole entry set by calling .next() until you reach the last. while (iterator.hasNext()) { lastElement = iterator.next() }
edit: However, if you're willing to go beyond the JavaSE API, Apache Commons Collections has its own LinkedMap implementa...
How to 'insert if not exists' in MySQL?
... any AUTO_INCREMENT column with failed insert. Probably because it's not really failed, but UPDATE'd.
– not2qubit
Oct 29 '13 at 21:36
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Reset Entity-Framework Migrations
... I used IgnoreChanges on the initial migration, but now I want to delete all my migrations and start with an initial migration with all of the logic.
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Is it possible to make relative link to image in a markdown file in a gist?
...rves a rel=canonical link. I wouldn't bet on Github to never change this!
All internal gist links (e.g. from user's page https://gist.github.com/cben/) omit the trailing slash :-(
Gists in Google search results omit the trailing slash :-(
(You could use relative path 46d9536baacb7c5d196c/raw/dodg...