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Strings as Primary Keys in SQL Database [closed]
... you'll get by using a string on smaller tables will be minuscule to the headaches that you can have by having an integer that doesn't mean anything in relation to the data.
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How do I represent a time only value in .NET?
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Jon SkeetJon Skeet
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Binding a Button's visibility to a bool value in ViewModel
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Assuming AdvancedFormat is a bool, you need to declare and use a BooleanToVisibilityConverter:
<!-- In your resources section of the XAML -->
<BooleanToVisibilityConverter x:Key="BoolToVis" />
<!-- In your Button decl...
Android ListView not refreshing after notifyDataSetChanged
...per.onResume();
items.clear();
items = dbHelper.getItems(); // reload the items from database
adapter.notifyDataSetChanged();
}
what you just have updated before calling notifyDataSetChanged() is not the adapter's field private List<Item> items; but the identically declared field...
How to put multiple statements in one line?
...-colon:
for i in range(10): print "foo"; print "bar"
But as soon as you add a construct that introduces an indented block (like if), you need the line break. Also,
for i in range(10): print "i equals 9" if i==9 else None
is legal and might approximate what you want.
As for the try ... except ...
Converting string into datetime
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user2357112 supports Monica
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answered Jan 21 '09 at 18:08
Patrick HarringtonPatrick ...
How to query as GROUP BY in django?
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jb.
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answered Mar 10 '09 at 11:08
Guðmundur HGuðmundur H
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How can I limit a “Run Script” build phase to my release configuration?
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Jason CocoJason Coco
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EF Code First “Invalid column name 'Discriminator'” but no inheritance
...not be saved to the DB.
The solution is quite simple and you just need to add [NotMapped] as an attribute of the derived class.
Example:
class Person
{
public string Name { get; set; }
}
[NotMapped]
class PersonViewModel : Person
{
public bool UpdateProfile { get; set; }
}
Now, even if...
使用App Inventor扩展实现多点触控：Rotation Detector · App Inventor 2 中文网
...r extension
App Inventor does not have multitouch capabilities built in. Adding multitouch is a popular request, and MIT App Inventor might eventually include it in the system. This note illustrates how to use App Inventor extensions to implement a RotationDetector component that people can use to...