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How to design a product table for many kinds of product where each product has many parameters
...the type hierarchy you describe:
Single Table Inheritance: one table for all Product types, with enough columns to store all attributes of all types. This means a lot of columns, most of which are NULL on any given row.
Class Table Inheritance: one table for Products, storing attributes common to...
Django - limiting query results
...s are lazy. That means a query will hit the database only when you specifically ask for the result.
So until you print or actually use the result of a query you can filter further with no database access.
As you can see below your code only executes one sql query to fetch only the last 10 items.
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How do you log server errors on django sites
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Well, when DEBUG = False, Django will automatically mail a full traceback of any error to each person listed in the ADMINS setting, which gets you notifications pretty much for free. If you'd like more fine-grained control, you can write and add to your settings a middlew...
Why should we NOT use sys.setdefaultencoding(“utf-8”) in a py script?
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As per the documentation: This allows you to switch from the default ASCII to other encodings such as UTF-8, which the Python runtime will use whenever it has to decode a string buffer to unicode.
This function is only available at Python start-up time,...
Should I git ignore xcodeproject/project.pbxproj file?
...odeproj
For non-SwiftPM answer - see below.
This file holds the list of all the files in the project, settings of targets and which files belong to which targets. It's probably the meatiest file in project bundle. You should not ignore this file. There are few points for this:
You may not want ...
Preventing Laravel adding multiple records to a pivot table
...ems()->where('foreign_key', $foreignKey)->count() Which, well, actually performs an additional query too '^^ But I don't need to fetch and hydrate the whole collection unless I really need it.
– Silence
May 24 '15 at 13:57
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C# short/long/int literal format?
... // uint
var ul = 1UL; // ulong
var l = 1L; // long
I think that's all... there are no literal specifiers for short/ushort/byte/sbyte
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Remote Connections Mysql Ubuntu
...'mypass';
CREATE USER 'myuser'@'%' IDENTIFIED BY 'mypass';
then,
GRANT ALL ON *.* TO 'myuser'@'localhost';
GRANT ALL ON *.* TO 'myuser'@'%';
and finally,
FLUSH PRIVILEGES;
EXIT;
If you don't have the same user created as above, when you logon locally you may inherit base localhost privileg...
Why is the .bss segment required?
...Imagine that your C program runs on an embedded system, where the code and all constants are saved in true ROM (flash memory). In such systems, an initial "copy-down" must be executed to set all static storage duration objects, before main() is called. It will typically go like this pseudo:
for(i=0...
What is the best Distributed Brute Force countermeasure?
...so far I'm winning (so to speak). But I've run into a pretty non-trivial challenge (one that most auth libraries miss entirely, but I insist on handling it properly): how to deal intelligently with large-scale, distributed, variable-username brute-force attacks .
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