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Grouped LIMIT in PostgreSQL: show the first N rows for each group?
I need to take the first N rows for each group, ordered by custom column.
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Can git automatically switch between spaces and tabs?
I use tabs for indentation in my python programs, but I would like to collaborate (using git) with people who use spaces instead.
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How update the _id of one MongoDB Document?
I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get:
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B-Tree vs Hash Table
In MySQL, an index type is a b-tree, and access an element in a b-tree is in logarithmic amortized time O(log(n)) .
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Output array to CSV in Ruby
It's easy enough to read a CSV file into an array with Ruby but I can't find any good documentation on how to write an array into a CSV file. Can anyone tell me how to do this?
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Putting text in top left corner of matplotlib plot
...t (or top right) corner of a matplotlib figure, e.g. where a top left legend would be, or on top of the plot but in the top left corner? E.g. if it's a plt.scatter(), then something that would be within the square of the scatter, put in the top left most corner.
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How to track down log4net problems
I use log4net all the time, but one thing I've never figured out is how to tell what's going on on the inside. For example, I've got a console appender and a database appender in my project. I made a few changes to the database and the code, and now the database appender doesn't work anymore. I'll f...
Show an image preview before upload
In my HTML form I have input filed with type file for example :
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Can you resolve an angularjs promise before you return it?
...n that returns a promise. But there are times when the information requested is available immediately. I want to wrap it in a promise so that the consumer doesn't need to make a decision.
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Is there any way in C# to override a class method with an extension method?
There have been occasions where I would want to override a method in a class with an extension method. Is there any way to do that in C#?
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