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Task vs Thread differences [duplicate]
... to parallel programming. There are two classes available in .NET: Task and Thread .
4 Answers
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Django admin: how to sort by one of the custom list_display fields that has no database field
...ustom manager for Customer which includes the number of orders aggregated, and then setting admin_order_field to that aggregate, ie
from django.db import models
class CustomerManager(models.Manager):
def get_query_set(self):
return super(CustomerManager, self).get_query_set().annotat...
How do you determine the ideal buffer size when using FileInputStream?
I have a method that creates a MessageDigest (a hash) from a file, and I need to do this to a lot of files (>= 100,000). How big should I make the buffer used to read from the files to maximize performance?
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How to perform runtime type checking in Dart?
...
is and is! can be found in the Operators section of the Dart language tour.
– Curly
Jun 25 '19 at 16:02
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What is the equivalent of “none” in django templates?
...
None, False and True all are available within template tags and filters. None, False, the empty string ('', "", """""") and empty lists/tuples all evaluate to False when evaluated by if, so you can easily do
{% if profile.user.first_nam...
ValueError : I/O operation on closed file
Here, p is a dictionary, w and c both are strings.
2 Answers
2
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Can I concatenate multiple MySQL rows into one field?
...048;
Of course, you can change 2048 according to your needs. To calculate and assign the value:
SET group_concat_max_len = CAST(
(SELECT SUM(LENGTH(hobbies)) + COUNT(*) * LENGTH(', ')
FROM peoples_hobbies
GROUP BY person_id)
AS UNSIGNED
);
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Abstract Class vs Interface in C++ [duplicate]
... about C++. As you know, there is no clear distinction between interface and abstract class in C++ unlike Java and C#. When would it be more preferrable to use an interface instead of an abstract class in C++? Could you give some examples?
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Custom attributes - Yea or nay?
Recently I have been reading more and more about people using custom attributes in their HTML tags, mainly for the purpose of embedding some extra bits of data for use in javascript code.
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How to prevent line breaks in list items using CSS
...re space by setting li's width to greater values.
[1] § 3. White Space and Wrapping: the white-space property - W3 CSS Text Module Level 3
[2] white-space - CSS: Cascading Style Sheets | MDN
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