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differentiate null=True, blank=True in django
When we add a database field in django we generally write:
18 Answers
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How SID is different from Service name in Oracle tnsnames.ora
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Quote by @DAC
In short: SID = the unique name of
your DB, ServiceName = the alias used
when connecting
Not strictly true. SID = unique name of the INSTANCE (eg the oracle process running on the machine). Oracle considers the "Databas...
Creating an abstract class in Objective-C
I'm originally a Java programmer who now works with Objective-C. I'd like to create an abstract class, but that doesn't appear to be possible in Objective-C. Is this possible?
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When should I use a List vs a LinkedList
When is it better to use a List vs a LinkedList ?
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“Cannot evaluate expression because the code of the current method is optimized” in Visual Studio 20
I am using Visual Studio 2010 in debug mode and I have "optimize code" unchecked. I can't quick watch (or hover on) any variable in the debugger. I get this error "Cannot evaluate expression because the code of the current method is optimized".
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Is Fortran easier to optimize than C for heavy calculations?
...ets. The performance difference comes from the fact that Fortran says aliasing is not allowed, unless an EQUIVALENCE statement is used. Any code that has aliasing is not valid Fortran, but it is up to the programmer and not the compiler to detect these errors. Thus Fortran compilers ignore possible ...
Role-based access control (RBAC) vs. Claims-based access control (CBAC) in ASP.NET MVC
What are the main benefits of using CBAC vs. RBAC ? When is it better to use CBAC and when is it better to use RBAC?
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Is there a performance difference between i++ and ++i in C++?
...e have the question is there a performance difference between i++ and ++i in C?
17 Answers
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How to delete items from a dictionary while iterating over it?
Is it legitimate to delete items from a dictionary in Python while iterating over it?
10 Answers
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Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign
I make an outer join and executed successfully in the informix database but I get the following exception in my code:
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