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How to create a unique index on a NULL column?
...nullable columns" is valid; to actually implement it in any relational database we just have to bear in mind that this kind of databases are meant to be normalized to properly work, and normalization usually involves the addition of several (non-entity) extra tables to establish relationships betwee...
Which characters need to be escaped in HTML?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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E731 do not assign a lambda expression, use a def
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What's the idiomatic syntax for prepending to a short python list?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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What is Autoloading; How do you use spl_autoload, __autoload and spl_autoload_register?
...er('MyAutoloader::HelperLoader');
spl_autoload_register('MyAutoloader::DatabaseLoader');
class MyAutoloader
{
public static function ClassLoader($className)
{
//your loading logic here
}
public static function LibraryLoader($className)
{
//your loading logic ...
Why does the JVM still not support tail-call optimization?
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How do I create a WPF Rounded Corner container?
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VB.Net code based implementation of kobusb's Border control solution. I used it to populate a ListBox of Button controls. The Button controls are created from MEF extensions. Each extension uses MEF's ExportMetaData attribute for a Descr...
What's wrong with nullable columns in composite primary keys?
... word of caution: Having nullable foreign keys is not clean relational database design.
If there are two entities A and B where A can optionally be related to B, the clean solution is to create a resolution table (let's say AB). That table would link A with B: If there is a relationship then it wou...
How to make Twitter Bootstrap menu dropdown on hover rather than click
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I created a pure on hover dropdown menu based on the latest (v2.0.2) Bootstrap framework that has support for multiple submenus and thought I'd post it for future users:
body {
padding-top: 60px;
padding-bottom: 40px;
}
.sidebar-nav {
padding: 9px...
Understanding events and event handlers in C#
... information, you can use a class derived from EventArgs (EventArgs is the base by convention). For example, if you look at some of the events defined on Control in WinForms, or FrameworkElement in WPF, you can see examples of events that pass additional information to the event handlers.
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