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Convert Rows to columns using 'Pivot' in SQL Server
I have read the stuff on MS pivot tables and I am still having problems getting this correct.
8 Answers
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Show an image preview before upload
In my HTML form I have input filed with type file for example :
5 Answers
5
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NULL vs nil in Objective-C
In observeValueForKeyPath:ofObject:change:context: - why do the docs use NULL instead of nil when not specifying a context pointer?
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Find rows with multiple duplicate fields with Active Record, Rails & Postgres
What is the best way to find records with duplicate values across multiple columns using Postgres, and Activerecord?
5 Answ...
Why would an Enum implement an Interface?
I just found out that Java allows enums to implement an interface. What would be a good use case for that?
16 Answers
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How to get process ID of background process?
...rom my shell script, and I would like to kill this process when my script finishes.
7 Answers
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Is there a `pointer-events:hoverOnly` or similar in CSS?
Just been playing about with pointer-events property in CSS.
7 Answers
7
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Why can a function modify some arguments as perceived by the caller, but not others?
I'm trying to understand Python's approach to variable scope. In this example, why is f() able to alter the value of x , as perceived within main() , but not the value of n ?
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Change Placeholder Text using jQuery
I am using a jQuery placeholder plugin(https://github.com/danielstocks/jQuery-Placeholder). I need to change the placeholder text with the change in dropdown menu. But it is not changing. Here is the code:
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Is Ruby pass by reference or by value?
@user object adds errors to the lang_errors variable in the update_lanugages method.
when I perform a save on the @user object I lose the errors that were initially stored in the lang_errors variable.
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