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Chaining multiple filter() in Django, is this a bug?
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The way I understand it is that they are subtly different by design (and I am certainly open for correction): filter(A, B) will first filter according to A and then subfilter according to B, while filter(A).filter(B) will return a row that ma...
What do helper and helper_method do?
... This is used for any method that you need to access from both controllers and helpers/views (standard helper methods are not available in controllers). e.g. common use case:
#application_controller.rb
def current_user
@current_user ||= User.find_by_id!(session[:user_id])
end
helper_method :curre...
What are the advantages of NumPy over regular Python lists?
... single-precision floats in the cells would fit in 4 MB. Access in reading and writing items is also faster with NumPy.
Maybe you don't care that much for just a million cells, but you definitely would for a billion cells -- neither approach would fit in a 32-bit architecture, but with 64-bit build...
Difference between git pull --rebase and git pull --ff-only
Let's say origin/master has commit A--B--C and my local/master has commit A--B--D .
1 Answer
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Re-raise exception with a different type and message, preserving existing information
I'm writing a module and want to have a unified exception hierarchy for the exceptions that it can raise (e.g. inheriting from a FooError abstract class for all the foo module's specific exceptions). This allows users of the module to catch those particular exceptions and handle them distinctly,...
Is there a built in function for string natural sort?
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Natsort is a great library, should be added to python standard library! :-)
– Mitch McMabers
Oct 24 '19 at 5:03
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Random record from MongoDB
I am looking to get a random record from a huge (100 million record) mongodb .
26 Answers
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JavaScript arrays braces vs brackets
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The first and third are equivalent and create a new array. The second creates a new empty object, not an array.
var myArray = []; //create a new array
var myArray = {}; //creates **a new empty object**
var myArray = new Array(); //cre...
Fragment transaction animation: slide in and slide out
...animate transaction between fragments. I've used this method for animation and it works:
5 Answers
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JPA or JDBC, how are they different?
I am learning Java EE and I downloaded the eclipse with glassfish for the same. I saw some examples and also read the Oracle docs to know all about Java EE 5. Connecting to a database was very simple. I opened a dynamic web project, created a session EJB , I used EntityManager and with the get meth...