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How to design a database for User Defined Fields?
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If performance is the primary concern, I would go with #6... a table per UDF (really, this is a variant of #2). This answer is specifically tailored to this situation and the description of the data distribution and access patterns ...
What is the purpose of Flask's context stacks?
I've been using the request/application context for some time without fully understanding how it works or why it was designed the way it was. What is the purpose of the "stack" when it comes to the request or application context? Are these two separate stacks, or are they both part of one stack? Is ...
How to check if a file exists in Documents folder?
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Swift 3:
let documentsURL = try! FileManager().url(for: .documentDirectory,
in: .userDomainMask,
appropriateFor: nil,
create: true)
... gives you a f...
How do I use arrays in C++?
...y everywhere. C++ provides abstractions that are easier to use and less error-prone ( std::vector<T> since C++98 and std::array<T, n> since C++11 ), so the need for arrays does not arise quite as often as it does in C. However, when you read legacy code or interact with a library wri...
Should ol/ul be inside or outside?
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The short answer is that ol elements are not legally allowed inside p elements.
To see why, let's go to the spec! If you can get comfortable with the HTML spec, it will answer many of your questions and curiosities. You want to kno...
Redis: possible to expire an element in an array or sorted set?
... them get auto removed 1 hour after insertion. Is that currently possible, or would it require running a cron job to do the purging manually?
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Checking if a key exists in a JavaScript object?
How do I check if a particular key exists in a JavaScript object or array?
22 Answers
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Image Processing: Algorithm Improvement for 'Coca-Cola Can' Recognition
One of the most interesting projects I've worked on in the past couple of years was a project about image processing . The goal was to develop a system to be able to recognize Coca-Cola 'cans' (note that I'm stressing the word 'cans', you'll see why in a minute). You can see a sample below, with ...
Jinja2 template variable if None Object set a default value
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Use the none builtin function (http://jinja.pocoo.org/docs/templates/#none):
{% if p is not none %}
{{ p.User['first_name'] }}
{% else %}
NONE
{%endif %}
or
{{ p.User['first_name'] if p != None else 'NONE' }}
or if you need an empty string:
{{ p.User['first...
Timertask or Handler
Let's say that I want to perform some action every 10 seconds and it doesn't necessarily need to update the view.
3 Answer...