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Is it possible to Pivot data using LINQ?
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GroupBy in Linq does not work the same as SQL. In SQL, you get the key and aggregates (row/column shape). In Linq, you get the key and any elements as children of the key (hierarchical shape). To pivot, you must project the hierarchy back into a row/column form of your choosing.
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.NET HashTable Vs Dictionary - Can the Dictionary be as fast?
I am trying to figure out when and why to use a Dictionary or a HashTable. I have done a bit of a search on here and have found people talking about the generic advantages of the Dictionary which I totally agree with, which leads the boxing and unboxing advantage for a slight performance gain.
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How do you bind an Enum to a DropDownList control in ASP.NET?
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I probably wouldn't bind the data as it's an enum, and it won't change after compile time (unless I'm having one of those stoopid moments).
Better just to iterate through the enum:
Dim itemValues As Array = System.Enum.GetValues(GetType(Response))
Dim itemNames As Array...
Sorting list based on values from another list?
...t should be: The list is ordered regarding the first element of the pairs, and the comprehension extracts the 'second' element of the pairs.
– MasterControlProgram
Oct 6 '17 at 14:31
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How to exit if a command failed?
I am a noob in shell-scripting. I want to print a message and exit my script if a command fails. I've tried:
8 Answers
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Git Symlinks in Windows
Our developers use a mix of Windows and Unix based OS's. Therefore, symlinks created on Unix machines become a problem for Windows developers. In windows (msysgit), the symlink is converted to a text file with a path to the file it points to. Instead, I'd like to convert the symlink into an actual W...
Extract subset of key-value pairs from Python dictionary object?
...bigdict.get(k, None) for k in ('l', 'm', 'n')}
If you're using Python 3, and you only want keys in the new dict that actually exist in the original one, you can use the fact to view objects implement some set operations:
{k: bigdict[k] for k in bigdict.keys() & {'l', 'm', 'n'}}
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Predicate Delegates in C#
... answered Feb 17 '09 at 11:45
Andrew HareAndrew Hare
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HtmlSpecialChars equivalent in Javascript?
Apparently, this is harder to find than I thought it would be. And it even is so simple...
16 Answers
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Difference between exit() and sys.exit() in Python
In Python, there are two similarly-named functions, exit() and sys.exit() . What's the difference and when should I use one over the other?
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