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Can a foreign key be NULL and/or duplicate?
...inition. 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 have a database that stores sales proposals. Suppose further that each proposal only has one sales person assigned and one client. So your proposal tab...
Is there an alternative to bastard injection? (AKA poor man's injection via default constructor)
...nough to advertise that users can override the dependency, as it's a well-known pattern, but I'll grant that overloaded constructors are marginally more 'in your face' :)
– Mark Seemann
Jul 20 '11 at 7:21
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How to remove from a map while iterating it?
...roduces the loop variable that is directly usable as the value, and so no knowledge of the container is required inside the loop. This is a clue to the intended usage of the RBFL for loops that do not have to know about the container. Erasing is the complete opposite situation, where it's all about ...
How do you add a Dictionary of items into another Dictionary
...alue(value, forKey:key)
}
}
}
dict1.update(dict2)
// dict1 is now ["a" : "foo", "b" : "bar]
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Difference between Divide and Conquer Algo and Dynamic Programming
...iginal solution and the technique of storing the sub-problem solutions is known as memoization.
You may think of DP = recursion + re-use
A classic example to understand the difference would be to see both these approaches towards obtaining the nth fibonacci number. Check this material from MIT.
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What is Express.js?
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Express.js is a Node.js framework. It's the most popular framework as of now (the most starred on NPM).
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It's built around configuration and granular simplicity of Connect middleware. Some people compare Express.js to Ruby Sinatra vs. the bulky and opinionated Ruby on Rails.
2) What is the...
Casting a variable using a Type variable
...pe intType = typeof(Int32);
object value1 = 1000.1;
// Variable value2 is now an int with a value of 1000, the compiler
// knows the exact type, it is safe to use and you will have autocomplete
int value2 = Convert.ChangeType(value1, intType);
// Variable value3 is now an int with a value of 1000...
What exactly do “u” and “r” string flags do, and what are raw string literals?
While asking this question , I realized I didn't know much about raw strings. For somebody claiming to be a Django trainer, this sucks.
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The Difference Between Deprecated, Depreciated and Obsolete [closed]
There is a lot of confusion about this and I'd like to know, what exactly is the difference between depreciated , deprecated and obsolete , in a programming context, but also in general.
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ASP.NET MVC partial views: input name prefixes
...r />
<input type="submit" value="Submit" />
</form>
Now this is complete. Set a breakpoint in the Create Post controller action to verify. Don't use this with lists however because it wont work. See my question on using EditorTemplates with IEnumerable for more on that.
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