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An item with the same key has already been added

... get this error whenever I submit the form also the action method is not being called because of this: 21 Answers ...
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Are nested transactions allowed in MySQL?

... InnoDB supports SAVEPOINTS. You can do the following: CREATE TABLE t_test (id INT NOT NULL PRIMARY KEY) ENGINE=InnoDB; START TRANSACTION; INSERT INTO t_test VALUES (1); SELECT * FROM t_test; id --- 1 SAVEPOI...
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How do I convert a String object into a Hash object?

I have a string which looks like a hash: 13 Answers 13 ...
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Handling optional parameters in javascript

... 2) { // if only two arguments were supplied if (Object.prototype.toString.call(parameters) == "[object Function]") { callback = parameters; } } //... } You can also use the arguments object in this way: function getData (/*id, parameters, callback*/) { var id = arguments[0],...
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How set background drawable programmatically in Android

...drawable.ready); is correct. Another way to achieve it is to use the following: final int sdk = android.os.Build.VERSION.SDK_INT; if(sdk < android.os.Build.VERSION_CODES.JELLY_BEAN) { layout.setBackgroundDrawable(ContextCompat.getDrawable(context, R.drawable.ready) ); } else { layout.set...
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How to scroll to bottom in a ScrollView on activity startup

I am displaying some data in a ScrollView. On activity startup (method onCreate) I fill the ScrollView with data and want to scroll to the bottom. ...
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How do I add indices to MySQL tables?

... ALTER TABLE `table` ADD INDEX `product_id_index` (`product_id`) Never compare integer to strings in MySQL. If id is int, remove the quotes. share | ...
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How Should I Declare Foreign Key Relationships Using Code First Entity Framework (4.1) in MVC3?

I have been searching for resources on how to declare foreign key relationships and other constraints using code first EF 4.1 without much luck. Basically I am building the data model in code and using MVC3 to query that model. Everything works via MVC which is great (kudos to Microsoft!) but now I ...
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LINQ's Distinct() on a particular property

I am playing with LINQ to learn about it, but I can't figure out how to use Distinct when I do not have a simple list (a simple list of integers is pretty easy to do, this is not the question). What I if want to use Distinct on a list of an Object on one or more properties of the object? ...
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NSUserDefaults not cleared after app uninstall on simulator

...second time the user enters my application, so to keep the run count I'm using NSUserDefaults . I have implemented the following code in my rootViewController 's viewDidLoad method: ...