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ORA-12505, TNS:listener does not currently know of SID given in connect descriptor
I have installed Oracle 11g Express Edition Release 2 in my windows 7 64 bit OS and tried to execute JDBC program, then I got the following error:
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Functional programming - is immutability expensive? [closed]
...’d like to clarify some points.
The “in-place” quicksort isn’t really in-place (and quicksort is not by definition in-place). It requires additional storage in the form of stack space for the recursive step, which is in the order of O(log n) in the best case, but O(n) in the worst case.
Im...
Issue with adding common code as git submodule: “already exists in the index”
...itory into place. If that's the case, you can do the following to unstage all of those files:
git rm -r --cached projectfolder
... and then add the submodule with:
git submodule add url_to_repo projectfolder
share
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Case insensitive string compare in LINQ-to-SQL
... accurate when you're trying to do case insensitive equality checks.
Ideally, the best way to do a case-insensitive equality check would be:
String.Equals(row.Name, "test", StringComparison.OrdinalIgnoreCase)
NOTE, HOWEVER that this does not work in this case! Therefore we are stuck with ToUpp...
What is stack unwinding?
...
Stack unwinding is usually talked about in connection with exception handling. Here's an example:
void func( int x )
{
char* pleak = new char[1024]; // might be lost => memory leak
std::string s( "hello world" ); // will be properly de...
Performing Breadth First Search recursively
...tion, but I suppose I could imagine some bizarre scenario where you're not allowed any heap space for some reason [some really bad custom memory manager? some bizarre runtime/OS issues?] while you still have access to the stack...)
Breadth-first traversal traditionally uses a queue, not a stack. T...
Fastest Way of Inserting in Entity Framework
...avingChanges (for each
record)..."
That's the worst thing you can do! Calling SaveChanges() for each record slows bulk inserts extremely down. I would do a few simple tests which will very likely improve the performance:
Call SaveChanges() once after ALL records.
Call SaveChanges() after for e...
nodeJs callbacks simple example
can any one give me a a simple example of nodeJs callbacks, I have already searched for the same on many websites but not able to understand it properly, Please give me a simple example.
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How to properly ignore exceptions
...is is true, but if you're not careful, you can run into subtle bugs (especially if you're doing something other than passing on StopIteration).
– Jason Baker
Apr 8 '09 at 17:46
17
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Setting an object to null vs Dispose()
...When you write a using statement, it's simply syntactic sugar for a try/finally block so that Dispose is called even if the code in the body of the using statement throws an exception. It doesn't mean that the object is garbage collected at the end of the block.
Disposal is about unmanaged resourc...