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MySQL “incorrect string value” error when save unicode string in Django
...per here)
To solve this you need to:
Change your MySQL database, table and columns to use the utf8mb4 character set (only available from MySQL 5.5 onwards)
Specify the charset in your Django settings file as below:
settings.py
DATABASES = {
'default': {
'ENGINE':'django.db.backen...
Difference between EXISTS and IN in SQL?
What is the difference between the EXISTS and IN clause in SQL?
21 Answers
21
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How do I send a file as an email attachment using Linux command line?
... that uses mysqldump to back up each of my MySQL databases to .sql files and packages them together as a compressed .tar file. The next step I want to accomplish is to send that tar file through email to a remote email server for safekeeping. I've been able to send the raw script in the body an ...
What's the simplest way to test whether a number is a power of 2 in C++?
...will want to check for it explicitly.
http://www.graphics.stanford.edu/~seander/bithacks.html has a large collection of clever bit-twiddling algorithms, including this one.
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MYSQL OR vs IN performance
... not believe people who give their "opinion", science is all about testing and evidence.
I ran a loop of 1000x the equivalent queries (for consistency, I used sql_no_cache):
IN: 2.34969592094s
OR: 5.83781504631s
Update:
(I don't have the source code for the original test, as it was 6 years ago, ...
How to compare a local git branch with its remote branch?
How can I see the diff between a local branch and a remote branch?
22 Answers
22
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How can I parse a JSON file with PHP? [duplicate]
...array. Plus, the entire thing is capsuled in OOP, so you have better reuse and you can easily mock it in UnitTests plus you can stack Iterators with other iterators doing different things, like limiting, caching, filtering and so on.. in addition to any custom iterators you might want to create.
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How to open an elevated cmd using command line for Windows?
How do I open a elevated command prompt using command lines on a normal cmd?
22 Answers
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Which exception should I raise on bad/illegal argument combinations in Python?
...tion..
def import_to_orm(name, save=False, recurse=False):
if recurse and not save:
raise ValueError("save must be True if recurse is True")
There's really no point in doing class BadValueError(ValueError):pass - your custom class is identical in use to ValueError, so why not use that...
Builder Pattern in Effective Java
...k. If it is non-static, it would require an instance of its owning class - and the point is not to have an instance of it, and even to forbid making instances without the builder.
public class NutritionFacts {
public static class Builder {
}
}
Reference: Nested classes
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