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What's the $unwind operator in MongoDB?
...ad" }
],
other : { foo : 5 }
}
Notice how tags is actually an array of 3 items, in this case being "fun", "good" and "fun".
What $unwind does is allow you to peel off a document for each element and returns that resulting document.
To think of this in a classical approach, it would be the equiv...
PostgreSQL: Can you create an index in the CREATE TABLE definition?
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Logger slf4j advantages of formatting with {} instead of string concatenation
...ust use either string concatenation or new Object[] { param1, param2, param3, ... }. There should be few enough of them that the performance is not as important.
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How to correctly close a feature branch in Mercurial?
...ure-x
$ hg ci -m merge
$ hg heads
(1 head)
$ hg branches
default 43:...
feature-x 41:...
(2 branches)
$ hg branches -a
default 43:...
(1 branch)
Another way is to close a feature branch before merging using an extra commit:
$ hg up feature-x
$ hg ci -m 'Closed branch feature...
Can I checkout github wikis like a git repository?
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138
You can now!
git clone https://github.com/user/project.wiki.git
or if you use ssh
git clone...
How to find elements with 'value=x'?
I need to remove element that have value="123" . I know that all elements with different values are located into #attached_docs , but I don't know how to select element with value="123" .
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How do I reference a Django settings variable in my models.py?
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edited Dec 3 '18 at 16:17
Arbazz Hussain
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answered O...
UITableView + Add content offset at top
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Santiago Prieto
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answered Jul 7 '10 at 3:04
jigzatjigzat
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Java8: Why is it forbidden to define a default method for a method from java.lang.Object
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answered Jun 3 '14 at 22:53
Brian GoetzBrian Goetz
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data type not understood
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JoshAdelJoshAdel
53.3k2222 gold badges125125 silver badges126126 bronze badges
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