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How to export collection to CSV in MongoDB?
...eOk();var keys = []; for(var key in db.${collectionArray[$i]}.find().sort({_id: -1}).limit(1)[0]) { keys.push(key); }; keys;" --quiet`;
# now use mongoexport with the set of keys to export the collection to csv
mongoexport --host $host -u $user -p $pass -d $dbname -c ${collectionArray[$i]} -...
In C/C++ what's the simplest way to reverse the order of bits in a byte?
...a script which outputs the table of the first 256 bytes and their reverse mapping. Yes, you're back to writing the reverse function, but now in your favourite scripting language, and it can be as nasty as you want -- you're going to throw it away as soon as it's done and you ran it once. Have the sc...
What is a practical use for a closure in JavaScript?
...updateClickCount()">click me</button>
Now there could be many approaches like:
1) You could use a global variable, and a function to increase the counter:
var counter = 0;
function updateClickCount() {
++counter;
// do something with counter
}
But, the pitfall is that any s...
Is there a way to suppress JSHint warning for one given line?
I have a (single) case in my app were eval is used, and I would like to suppress JSHint warning only for this case.
3 Ans...
Copy/duplicate database without using mysqldump
...
I've cleaned-up this script by @jozjan and applied some of the comments regarding foreign and other keys to create this version on GIST gist.github.com/christopher-hopper/8431737
– Christopher
Jan 15 '14 at 7:08
...
How do I use vi keys in ipython under *nix?
...
Where do I add my custom key binding mappings?
– Aravinda
Jul 21 '16 at 12:17
My ...
What is the purpose of Serialization in Java?
...rializing it to another object achieves this goal.
Caching: Really just an application of the above, but sometimes an object takes 10 minutes to build, but would only take 10 seconds to de-serialize. So, rather than hold onto the giant object in memory, just cache it out to a file via serialization...
Get querystring from URL using jQuery [duplicate]
...ing = urlOrQueryString.substring(i+1);
if (queryString) {
return _mapUrlParams(queryString);
}
}
return {};
}
/**
* Helper function for `getUrlParams()`
* Builds the querystring parameter to value object map.
*
* @param queryString {string} - The full querystring, without th...
How to empty a list?
...explanation of del, I'd refer to the docs: docs.python.org/reference/simple_stmts.html#the-del-statement
– fortran
Sep 9 '09 at 16:28
14
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How do I install Maven with Yum?
...apache-maven
Next add the env variables to your ~/.bashrc file
export M2_HOME=/usr/local/apache-maven
export M2=$M2_HOME/bin
export PATH=$M2:$PATH
Execute these commands
source ~/.bashrc
6:. Verify everything is working with the following command
mvn -version
...