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Validation failed for one or more entities. See 'EntityValidationErrors' property for more details [
I am having this error when seeding my database with code first approach.
29 Answers
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INNER JOIN ON vs WHERE clause
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INNER JOIN is ANSI syntax which you should use.
It is generally considered more readable, especially when you join lots of tables.
It can also be easily replaced with an OUTER JOIN whenever a need arises.
The WHERE syntax ...
Java's final vs. C++'s const
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In C++ marking a member function const means it may be called on const instances. Java does not have an equivalent to this. E.g.:
class Foo {
public:
void bar();
void foo() const;
};
void test(const Foo& i) {
i...
Do you leave parentheses in or out in Ruby? [closed]
When possible.. do you leave parentheses in or out in Ruby?
9 Answers
9
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How to identify if a webpage is being loaded inside an iframe or directly into the browser window?
I am writing an iframe based facebook app. Now I want to use the same html page to render the normal website as well as the canvas page within facebook. I want to know if I can determine whether the page has been loaded inside the iframe or directly in the browser?
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How to compile and run C/C++ in a Unix console/Mac terminal?
How can I compile/run C or C++ in Unix console or a Mac terminal?
16 Answers
16
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Does every Core Data Relationship have to have an Inverse?
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In practice, I haven't had any data loss due to not having an inverse - at least that I am aware of. A quick Google suggests you should use them:
An inverse relationship doesn't just
make things more tidy, it's actuall...
Rails I18n validation deprecation warning
I just updated to rails 4.0.2 and I'm getting this warning:
5 Answers
5
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@class vs. #import
It is to my understanding that one should use a forward-class declaration in the event ClassA needs to include a ClassB header, and ClassB needs to include a ClassA header to avoid any circular inclusions. I also understand that an #import is a simple ifndef so that an include only happens once....
Classes residing in App_Code is not accessible
I have created a website in ASP.NET and have created a class and put it inside of the App_Code folder. However I cannot access this from my other pages. Does something need to be configured to allow this? I have made it work in previous projects, but not in this one, somehow.
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