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The relationship could not be changed because one or more of the foreign-key properties is non-nulla

...iginal parent including the child item collection var originalParent = _dbContext.ParentItems .Where(p => p.ID == parent.ID) .Include(p => p.ChildItems) .SingleOrDefault(); // We assume that the parent is still in the DB and don't check for null // Update s...
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How to write log base(2) in c/c++

... #define M_LOG2E 1.44269504088896340736 // log2(e) inline long double log2(const long double x){ return log(x) * M_LOG2E; } (multiplication may be faster than division) ...
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Spring Data JPA find by embedded object property

...Long twoId); and results in a query of the form: select ...... from one one_ left outer join two two_ on one_.two_id = two_.id where one_id = ? and two_.id = ? – TroJaN May 4 at 17:17 ...
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How to perform Callbacks in Objective-C

...newer) option is to use blocks: @interface MyClass: NSObject { void (^_completionHandler)(int someParameter); } - (void) doSomethingWithCompletionHandler:(void(^)(int))handler; @end @implementation MyClass - (void) doSomethingWithCompletionHandler:(void(^)(int))handler { // NOTE: copyin...
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PHP script - detect whether running under linux or Windows?

... Check the value of the PHP_OS constantDocs. It will give you various values on Windows like WIN32, WINNT or Windows. See as well: Possible Values For: PHP_OS and php_unameDocs: if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') { echo 'This is a s...
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How to download image using requests

...flate). You can force it to decompress for you anyway by setting the decode_content attribute to True (requests sets it to False to control decoding itself). You can then use shutil.copyfileobj() to have Python stream the data to a file object: import requests import shutil r = requests.get(settin...
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Unique constraint on multiple columns

...ied from technet's documentation, is in the form of: CONSTRAINT constraint_name UNIQUE [ CLUSTERED | NONCLUSTERED ] ( column [ ASC | DESC ] [ ,...n ] ) Therefore, the resuting table definition would be: CREATE TABLE [dbo].[user]( [userID] [int] IDENTITY(1,1) NOT NULL, [fcode] [int] ...
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In PHP, can you instantiate an object and call a method on the same line?

...So, if you declared a class like this : class Test { public function __construct($param) { $this->_var = $param; } public function myMethod() { return $this->_var * 2; } protected $_var; } You can then declare a function that returns an instance of that ...
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What are some uses of decltype(auto)?

...p;& auto x6a = { 1, 2 }; // decltype(x6a) is std::initializer_list<int> decltype(auto) x6d = { 1, 2 }; // error, { 1, 2 } is not an expression auto *x7a = &i; // decltype(x7a) is int* decltype(auto)*x7d = &i; // error, declared type is not plain declt...
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What can you do in MSIL that you cannot do in C# or VB.NET? [closed]

...etty much all over the place. Examine the IL for this: "let print x = print_any x". – MichaelGG Feb 24 '09 at 23:22 1 ...