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mongodb count num of distinct values per field/key
Is there a query for calculating how many distinct values a field contains in DB.
5 Answers
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What is “lifting” in Scala?
Sometimes when I read articles in the Scala ecosystem I read the term "lifting" / "lifted". Unfortunately, it is not explained what that exactly means. I did some research, and it seems that lifting has something to do with functional values or something like that, but I was not able to find a text ...
Using TortoiseSVN how do I merge changes from the trunk to a branch and vice versa?
I've been reading up on branching/merging with Subversion 1.5 using the excellent and free Version Control with Subversion book. I think that I understand how to use the Subversion command line client to perform the actions that I need most often, which are:
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Maven check for updated dependencies in repository
Is there a Maven plugin that allows you to check if there are newer versions of dependencies available in the repository?
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How to deserialize a list using GSON or another JSON library in Java?
I can serialize a List<Video> in my servlet on GAE, but I can't deserialize it. What am I doing wrong?
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How to set RelativeLayout layout params in code not in xml?
For example I want to add 3 buttons on screen: one align left, one align center, last one align right.
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How to pass an array into jQuery .data() attribute
Ok so I want to pass a very basic array into a jquery data attrubute server side like so:
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setNeedsLayout vs. setNeedsUpdateConstraints and layoutIfNeeded vs updateConstraintsIfNeeded
I know that the auto layout chain consists in basically 3 different process.
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Regex to check whether a string contains only numbers [duplicate]
I get false on both "123" and "123f" . I would like to check if the hash only contains numbers. Did I miss something?
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How do you execute an arbitrary native command from a string?
I can express my need with the following scenario: Write a function that accepts a string to be run as a native command.
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