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How do I perform the SQL Join equivalent in MongoDB?
...mmend specific use cases for $lookup, but at least as of 3.2 doing join is now possible with MongoDB.
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What is android:weightSum in android, and how does it work?
I want to know: What is android:weightSum and layout weight, and how do they work?
9 Answers
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Converting JSON data to Java object
... + "}]"
+ "}]"
+ "}";
// Now do the magic.
Data data = new Gson().fromJson(json, Data.class);
// Show it.
System.out.println(data);
}
}
class Data {
private String title;
private Long id;
private Boolean chi...
Android Emulator: Installation error: INSTALL_FAILED_VERSION_DOWNGRADE
...here the version number was higher than the copy you're working with right now. In either case, either:
uninstall the currently installed copy
or open up your phone's Settings > Application Manager to determine the version number for the installed app, and increment your <manifest android:v...
Is there a performance gain in using single quotes vs double quotes in ruby?
Do you know if using double quotes instead of single quotes in ruby decreases performance in any meaningful way in ruby 1.8 and 1.9.
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How do you remove duplicates from a list whilst preserving order?
...n that removes duplicates from list in Python, whilst preserving order? I know that I can use a set to remove duplicates, but that destroys the original order. I also know that I can roll my own like this:
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A generic list of anonymous class
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okay cool, now we need an example of replacing the new {} lines with a select statement. var list = sourceList.Select( o => new { ...
How do I find the next commit in git? (child/children of ref)
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The creator for Hudson (now Jenkins) Kohsuke Kawaguchi just published (November 2013):
kohsuke / git-children-of:
Given a commit, find immediate children of that commit.
#!/bin/bash -e
# given a commit, find immediate children of that commit.
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MongoDB mongorestore failure: locale::facet::_S_create_c_locale name not valid
...-8"
LC_MEASUREMENT="en_US.UTF-8"
LC_IDENTIFICATION="en_US.UTF-8"
LC_ALL=
Now mongo also should do fine.
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How efficient is locking an unlocked mutex? What is the cost of a mutex?
... itself manages the scheduling and context switches, this makes sense. But now I have a rough imagination about what the mutex lock/unlock will do internally.
– Albert
Sep 6 '10 at 21:55
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