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SQLAlchemy: cascade delete
...use that is where you defined your relationship (it doesn't care that you called it "Child" of course).
If you define the relationship on the Parent class instead, it will work:
children = relationship("Child", cascade="all,delete", backref="parent")
(note "Child" as a string: this is allowed wh...
How to redirect to a 404 in Rails?
...ou want to show a 404 page, create a render_404 method (or not_found as I called it) in ApplicationController like this:
def not_found
raise ActionController::RoutingError.new('Not Found')
end
Rails also handles AbstractController::ActionNotFound, and ActiveRecord::RecordNotFound the same way....
Determine if variable is defined in Python [duplicate]
...ime? This is not always obvious because (1) the variable could be conditionally set, and (2) the variable could be conditionally deleted. I'm looking for something like defined() in Perl or isset() in PHP or defined? in Ruby.
...
Access parent DataContext from DataTemplate
... this exact code in my project but it's leaking ViewModels (Finalizer not called, Command binding seems to retain DataContext). Can you verify that this issue exists for you as well?
– Joris Weimar
Jan 22 '13 at 11:05
...
What's with 181783497276652981 and 8682522807148012 in Random (Java 7)?
...d have worked as well as these two numbers?
Not every number would be equally "good". So, no.
Seeding Strategies
There are differences in the default-seeding schema between different versions and implementation of the JRE.
public Random() { this(System.currentTimeMillis()); }
public Ra...
How to manage client-side JavaScript dependencies? [closed]
...anage dependencies on the server side, I could not find any that satisfies all my needs to have a coherent client side JavaScript dependency management workflow. I want to satisfy these 5 requirements:
...
How do I replace whitespaces with underscore?
...s, such as \t or a non-breaking space.
– Roberto Bonvallet
Jun 17 '09 at 15:49
13
Yes you are cor...
How do I find the location of my Python site-packages directory?
...ib"])'
The per user site-packages directory (PEP 370) is where Python installs your local packages:
python -m site --user-site
If this points to a non-existing directory check the exit status of Python and see python -m site --help for explanations.
Hint: Running pip list --user or pip freeze -...
User Authentication in ASP.NET Web API
...tems provide an answers to the questions:
Who is the user?
Is the user really who he/she represents himself to be?
Authorization is the mechanism by which a system determines what level of access a particular authenticated user should have to secured resources controlled by the system. For exampl...
I want to execute shell commands from Maven's pom.xml
...a while to find this simple syntactical mistake. Maven's error output is really not that helpful.
– joergl
Aug 29 '16 at 8:23
1
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