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Get records with max value for each group of grouped SQL results
...also the problems of returning multiple rows when there are more than one with the same maximum value (as the other answers would do)
Note: This is a mysql-only solution. All other databases I know will throw an SQL syntax error with the message "non aggregated columns are not listed in the group by...
How to convert from System.Enum to base integer?
... to create a generic method for converting any System.Enum derived type to its corresponding integer value, without casting and preferably without parsing a string.
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What are Flask Blueprints, exactly?
...emplate for generating a "section" of a web application. You can think of it as a mold:
You can take the blueprint and apply it to your application in several places. Each time you apply it the blueprint will create a new version of its structure in the plaster of your application.
# An example...
Fast way to get image dimensions (not filesize)
...ooking for a fast way to get the height and width of an image in pixels. It should handle at least JPG, PNG and TIFF, but the more the better. I emphasize fast because my images are quite big (up to 250 MB) and it takes soooo long to get the size with ImageMagick's identify because it obviousl...
Pure JavaScript Graphviz equivalent [closed]
... but the computations to figure out the maximum depth of each node, along with the layout of bezier lines that are optimized to minimize the number of intersecting edges when you are dealing with a graph rather than a tree of information. I would like to run this code both within a browser; I am aw...
Why do people say that Ruby is slow? [closed]
I like Ruby on Rails and I use it for all my web development projects. A few years ago there was a lot of talk about Rails being a memory hog and about how it didn't scale very well but these suggestions were put to bed by Gregg Pollack here.
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Should private helper methods be static if they can be static
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I prefer such helper methods to be private static; which will make it clear to the reader that they will not modify the state of the object. My IDE will also show calls to static methods in italics, so I will know the method is static without looking the signature.
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What is DOM Event delegation?
Can anyone please explain event delegation in JavaScript and how is it useful?
11 Answers
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How to get the first element of an array?
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@Andy There were no assumptions, as OP's question was quite clear and specific.
– John Hartsock
Aug 11 '15 at 0:36
5
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How to save an activity state using save instance state?
I've been working on the Android SDK platform, and it is a little unclear how to save an application's state. So given this minor re-tooling of the 'Hello, Android' example:
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