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Why do we need the “finally” clause in Python?
I am not sure why we need finally in try...except...finally statements. In my opinion, this code block
14 Answers
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Django Model - Case-insensitive Query / Filtering
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I solved it like this:
MyClass.objects.filter(name__iexact=my_parameter)
There is even a way to use it for substring search:
MyClass.objects.filter(name__icontains=my_parameter)
There's a link to the documentation.
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The difference between fork(), vfork(), exec() and clone()
...d I expected there to be a huge amount of information on this, but there really wasn't any solid comparison between the four calls.
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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How to get the next auto-increment id in mysql
... Thanks for the first two options.. But the third is just number two called from PHP.. Not sure what makes that faster on large databases...
– Gerard ONeill
Feb 12 '16 at 15:26
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How to generate a random string in Ruby
...).chr }.join
I spend too much time golfing.
(0...50).map { ('a'..'z').to_a[rand(26)] }.join
And a last one that's even more confusing, but more flexible and wastes fewer cycles:
o = [('a'..'z'), ('A'..'Z')].map(&:to_a).flatten
string = (0...50).map { o[rand(o.length)] }.join
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How to split a large text file into smaller files with equal number of lines?
...a large (by number of lines) plain text file that I'd like to split into smaller files, also by number of lines. So if my file has around 2M lines, I'd like to split it up into 10 files that contain 200k lines, or 100 files that contain 20k lines (plus one file with the remainder; being evenly divi...
SQL select join: is it possible to prefix all columns as 'prefix.*'?
...e is to assign a dummy column to separate each new table. This works especially well if you're looping through a result set for a list of columns in a scripting language such as Python or PHP.
SELECT '' as table1_dummy, table1.*, '' as table2_dummy, table2.*, '' as table3_dummy, table3.* FROM table...
appending array to FormData and send via AJAX
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add all type inputs to FormData
const formData = new FormData();
for (let key in form) {
Array.isArray(form[key])
? form[key].forEach(value => formData.append(key + '[]', value))
: formData.append(key, for...
Iterator invalidation rules
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C++17 (All references are from the final working draft of CPP17 - n4659)
Insertion
Sequence Containers
vector: The functions insert, emplace_back, emplace, push_back cause reallocation if the new size is greater than the old capa...