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Can a foreign key be NULL and/or duplicate?
...remember a Foreign key simply requires that the value in that field must exist first in a different table (the parent table). That is all an FK is by definition. Null by definition is not a value. Null means that we do not yet know what the value is.
Let me give you a real life example. Suppose you...
Which is better in python, del or delattr?
This may be silly, but it's been nagging the back of my brain for a while.
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Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
Regarding this .NET unhandled exception message:
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Find out whether Chrome console is open
I am using this little script to find out whether Firebug is open:
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Difference between EXISTS and IN in SQL?
What is the difference between the EXISTS and IN clause in SQL?
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ASP.NET Identity's default Password Hasher - How does it work and is it secure?
I am wondering wether the Password Hasher that is default implemented in the UserManager that comes with MVC 5 and ASP.NET Identity Framework, is secure enough? And if so, if you could explain to me how it works?
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Why no ICloneable?
Is there a particular reason why a generic ICloneable<T> does not exist?
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@Resource vs @Autowired
...ements Foo { .. }
And then:
@Inject @YourQualifier private Foo foo;
This makes less use of String-names, which can be misspelled and are harder to maintain.
As for the original question: both, without specifying any attributes of the annotation, perform injection by type. The difference is:
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Working with select using AngularJS's ng-options
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One thing to note is that ngModel is required for ngOptions to work... note the ng-model="blah" which is saying "set $scope.blah to the selected value".
Try this:
<select ng-model="blah" ng-options="item.ID as item.Title for item in items...
Retrieving a List from a java.util.stream.Stream in Java 8
...with Java 8 lambdas to easily filter collections. But I did not find a concise way to retrieve the result as a new list within the same statement. Here is my most concise approach so far:
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