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Why does my application spend 24% of its life doing a null check?
I've got a performance critical binary decision tree, and I'd like to focus this question on a single line of code. The code for the binary tree iterator is below with the results from running performance analysis against it.
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Difference between rake db:migrate db:reset and db:schema:load
The difference between rake db:migrate and rake db:reset is pretty clear in my head. The thing which I don't understand is how rake db:schema:load different from the former two.
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Should arrays be used in C++?
Since std::list and std::vector exist, is there a reason to use traditional C arrays in C++, or should they be avoided, just like malloc ?
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classical inheritance vs prototypal inheritance in javascript
I have googled so many links and can't get good idea about the difference between classical inheritance and prototypal inheritance?
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Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
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Why should I use core.autocrlf=true in Git?
I have a Git repository that is accessed from both Windows and OS X, and that I know already contains some files with CRLF line-endings. As far as I can tell, there are two ways to deal with this:
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SQL Server: Examples of PIVOTing String data
...SQL Server PIVOT examples. Most of the examples that I have found involve counting or summing up numbers. I just want to pivot some string data. For example, I have a query returning the following.
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Transaction isolation levels relation with locks on table
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What is the purpose of setting a key in data.table?
I am using data.table and there are many functions which require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
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IE10 renders in IE7 mode. How to force Standards mode?
On microsoft's site they claim that simple doctype declaration is enough. But even a document as short as this falls back to IE7 mode:
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