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Primary key or Unique index?
At work we have a big database with unique indexes instead of primary keys and all works fine.
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What is the difference between NULL, '\0' and 0?
In C, there appear to be differences between various values of zero -- NULL , NUL and 0 .
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What is the purpose of the reader monad?
The reader monad is so complex and seems to be useless. In an imperative language like Java or C++, there is no equivalent concept for the reader monad, if I am not mistaken.
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What is the difference between class and instance attributes?
Is there any meaningful distinction between:
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Modulo operation with negative numbers
In a C program i was trying the below operations(Just to check the behavior )
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Should an Enum start with a 0 or a 1?
Imagine I have defined the following Enum:
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How To Create a Flexible Plug-In Architecture?
A repeating theme in my development work has been the use of or creation of an in-house plug-in architecture. I've seen it approached many ways - configuration files (XML, .conf, and so on), inheritance frameworks, database information, libraries, and others. In my experience:
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Is there a difference between foreach and map?
Ok this is more of a computer science question, than a question based on a particular language, but is there a difference between a map operation and a foreach operation? Or are they simply different names for the same thing?
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What is a good Hash Function?
What is a good Hash function? I saw a lot of hash function and applications in my data structures courses in college, but I mostly got that it's pretty hard to make a good hash function. As a rule of thumb to avoid collisions my professor said that:
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Can a local variable's memory be accessed outside its scope?
I have the following code.
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