大约有 44,000 项符合查询结果（耗时：0.0447秒） [XML]
Get names of all keys in the collection
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You could do this with MapReduce:
mr = db.runCommand({
"mapreduce" : "my_collection",
"map" : function() {
for (var key in this) { emit(key, null); }
},
"reduce" : function(key, stuff) { return null; },
"out": "my_collection" + "_keys"
})
Then run distinct ...
How can I search for a multiline pattern in a file?
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This is much easier to understand and uses awk that comes with most *nix systems.
– Ali Karbassi
Jan 28 '11 at 3:12
25
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Cast Int to enum in Java
...lid ordinal for that enum.
Note that in Java enums actually are classes (and enum values thus are objects) and thus you can't cast an int or even Integer to an enum.
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When should I use the Visitor Design Pattern? [closed]
...dmit, I just don't get it. I read the wikipedia article for the pattern and I understand its mechanics but I'm still confused as to when I'd use it.
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Simple example of threading in C++
...sk1 says: " << msg;
}
int main()
{
// Constructs the new thread and runs it. Does not block execution.
thread t1(task1, "Hello");
// Do other things...
// Makes the main thread wait for the new thread to finish execution, therefore blocks its own execution.
t1.join();
}
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How to remove array element in mongodb?
...mber: '+1786543589455' } } }
);
It will find document with the given _id and remove the phone +1786543589455 from its contact.phone array.
You can use $unset to unset the value in the array (set it to null), but not to remove it completely.
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Render basic HTML view?
...ade
include plain.html
in views/plain.html
<!DOCTYPE html>
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and app.js can still just render jade:
res.render(index)
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How do I save and restore multiple variables in python?
I need to save about a dozen objects to a file and then restore them later.
I've tried to use a for loop with pickle and shelve but it didn't work right.
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Troubleshooting “Illegal mix of collations” error in mysql
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Another option is to use the BINARY operator:
BINARY str is the shorthand for CAST(str AS BINARY).
Your solution might look something like this:
SELECT * FROM table WHERE BINARY a = BINARY b;
or,
SELECT * FROM table ORDER BY BINARY a;
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libxml/tree.h no such file or directory
...rameworks section). On the Mac,
you'll find it at /usr/lib/libxml2.dylib and for the iPhone, you'll
want the
/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS4.0.sdk/usr/lib/libxml2.dylib
version.
Since libxml2 is a .dylib (not a nice friendly .framework) we still
have on...