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What does inverse_of do? What SQL does it generate?
...any of the following options:
:through
:foreign_key
class Author < ApplicationRecord
has_many :books, inverse_of: 'writer'
end
class Book < ApplicationRecord
belongs_to :writer, class_name: 'Author', foreign_key: 'author_id'
end
a = Author.first
b = a.books.first
a.first_name == b.w...
Django connection to PostgreSQL: “Peer authentication failed”
...
Had the same problem with a Rails app, and it was the same solution - the host needed to be configured in config/database.yml - that is to say, in that file I needed to add the line host: localhost (or wherever you postgres server is - mine was local)
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Grasping the Node JS alternative to multithreading
...read and set a callback when it's done which means that the read could be happening on a different thread/core while the main node.js program is doing something else.
But from a node.js point of view, it's entirely single threaded and won't directly use more than one core.
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Practical use of `stackalloc` keyword
... @MaxBarraclough Because you add the GC cost to heap allocations over the application lifetime. Total allocation cost = allocation + deallocation, in this case pointer bump + GC Heap, vs pointer bump + pointer decrement Stack
– Pop Catalin
Dec 18 '18 at 10:04
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Java - JPA - @Version annotation
...sage triggers creation of an entity and there are multiple instances of an application listens to the message. I just want to avoid the unique constraint violation error..
– Manu
Jan 19 '16 at 6:28
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Given a view, how do I get its viewController?
...ments the method by returning its view’s superview; UIWindow returns the application object, and UIApplication returns nil.
So, if you recurse a view’s nextResponder until it is of type UIViewController, then you have any view’s parent viewController.
Note that it still may not have a paren...
Django Rest Framework: Dynamically return subset of fields
...ds with e.g. fields=key1&fields=key2, which is a nice-to-have for ajax apps. It also has zero test coverage, which is somewhat unusual in OSS.
– wim
Dec 2 '16 at 17:03
1
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How to track down log4net problems
...how to tell what's going on on the inside. For example, I've got a console appender and a database appender in my project. I made a few changes to the database and the code, and now the database appender doesn't work anymore. I'll figure out why eventually, but it would help a lot if I could see wha...
Django: Get list of model fields?
...answers are outdated I'll try to update you on Django 2.2
Here posts- your app (posts, blog, shop, etc.)
1) From model link: https://docs.djangoproject.com/en/stable/ref/models/meta/
from posts.model import BlogPost
all_fields = BlogPost._meta.fields
#or
all_fields = BlogPost._meta.get_fields()
No...
What does [object Object] mean?
... [ In HTML5, IDs can start with digits.](whatwg.org/specs/web-apps/current-work/multipage/…)
– Matt Ball
Jan 20 '11 at 17:21
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