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Why does direction of index matter in MongoDB?
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MongoDB concatenates the compound key in some way and uses it as the key in a BTree.
When finding single items - The order of the nodes in the tree is irrelevant.
If you are returning a range of nodes - The elements close to each other will be down the same branches of th...
Recursion or Iteration?
...e is recursive call). Tail recursion should be recognized by the compiler and optimized to its iterative counterpart (while maintaining the concise, clear implementation you have in your code).
I would write the algorithm in the way that makes the most sense and is the clearest for the poor sucker...
How to deploy an ASP.NET Application with zero downtime
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You need 2 servers and a load balancer. Here's in steps:
Turn all traffic on Server 2
Deploy on Server 1
Test Server 1
Turn all traffic on Server 1
Deploy on Server 2
Test Server 2
Turn traffic on both servers
Thing is, even in this case yo...
Visual Studio 2010 isn't building before a run when there are code changes
...ing F5 (Start Debugging) for years to build the code (if its out of date), and then debug. This was working on VS 2010 also, however today it just start debugging without a build. Say I do a clean on the project, and then hit F5 instead of building it so it can run it throws an error message saying ...
Algorithm to generate all possible permutations of a list?
... left to right, all the permutations of the remaining items are generated (and each one is added with the current elements). This can be done recursively (or iteratively if you like pain) until the last item is reached at which point there is only one possible order.
So with the list [1,2,3,4] all ...
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...y ways to do this. This answer starts with what is quickly becoming the standard method, but also includes older methods and various other methods from answers to similar questions scattered around this site.
tmp <- data.frame(x=gl(2,3, labels=letters[24:25]),
y=gl(3,1,6, labe...
Piping both stdout and stderr in bash?
...t newer versions of bash have the &> operator, which (if I understand correctly), redirects both stdout and stderr to a file ( &>> appends to the file instead, as Adrian clarified).
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How do I clone a single branch in Git?
...g a shallow clone.
This makes git clone --depth 1 the easiest way to save bandwidth.
And since Git 1.9.0 (February 2014), shallow clones support data transfer (push/pull), so that option is even more useful now.
See more at "Is git clone --depth 1 (shallow clone) more useful than it makes out?".
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Capitalize only first character of string and leave others alone? (Rails)
I'm trying to get Rails to capitalize the first character of a string, and leave all the others the way they are. I'm running into a problem where "i'm from New York" gets turned into "I'm from new york."
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The input is not a valid Base-64 string as it contains a non-base 64 character
I have a REST service that reads a file and sends it to another console application after converting it to Byte array and then to Base64 string. This part works, but when the same stream is received at the application, it gets manipulated and is no longer a valid Base64 string. Some junk characters ...