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entity object cannot be referenced by multiple instances of IEntityChangeTracker. while adding relat
I am trying to save Employee details, which has references with City. But everytime I try to save my contact, which is validated I get the exception "ADO.Net Entity Framework An entity object cannot be referenced by multiple instances of IEntityChangeTracker"
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Best way to remove from NSMutableArray while iterating?
In Cocoa, if I want to loop through an NSMutableArray and remove multiple objects that fit a certain criteria, what's the best way to do this without restarting the loop each time I remove an object?
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Why there is no “Home” button in iPad simulator in iOS 5.1 SDK?
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I found this key combination may active slow motion (stackoverflow.com/questions/8624519/…), quite annoying
– Chris Chen
Mar 31 '12 at 15:20
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Is there a builtin confirmation dialog in Windows Forms?
I'd like to create a simple confirm dialog saying "Please check the information and if you're sure it's correct, click OK."
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Should methods that throw RuntimeException indicate it in method signature?
For example, many methods in frameworks/JDK might throw
7 Answers
7
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Class constants in python
In python, I want a class to have some "constants" (practically, variables) which will be common in all subclasses. Is there a way to do it with friendly syntax?
Right now I use:
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How can I control the width of a label tag?
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Using CSS, of course...
label { display: block; width: 100px; }
The width attribute is deprecated, and CSS should always be used to control these kinds of presentational styles.
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How to migrate back from initial migration in Django 1.7?
...els are poorly thought out. As I haven't committed the code the sensible thing would be to migrate the database to last good state and redo the migration with better models. In this case the last good state is database where the new app doesn't exist.
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Keep only first n characters in a string?
Is there a way in JavaScript to remove the end of a string?
7 Answers
7
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MySQL: Order by field size/length
... BY LENGTH(description) DESC;
The LENGTH function gives the length of string in bytes. If you want to count (multi-byte) characters, use the CHAR_LENGTH function instead:
SELECT * FROM TEST ORDER BY CHAR_LENGTH(description) DESC;
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