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Why are joins bad when considering scalability?
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Scalability is all about pre-computing (caching), spreading out, or paring down the repeated work to the bare essentials, in order to minimize resource use per work unit. To scale well, you don't do anything you don't need to in volume, and...
How to compare a local git branch with its remote branch?
...rbranch_path> <remotebranch_path>
You can git branch -a to list all branches (local and remote) then choose branch name from list (just remove remotes/ from remote branch name.
Example: git diff master origin/master (where "master" is local master branch and "origin/master" is a remote n...
Copy the entire contents of a directory in C#
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Much easier
//Now Create all of the directories
foreach (string dirPath in Directory.GetDirectories(SourcePath, "*",
SearchOption.AllDirectories))
Directory.CreateDirectory(dirPath.Replace(SourcePath, DestinationPath));
//Copy all the files...
How do I iterate over the words of a string?
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Actually, this can work just fine with other delimiters (though doing some is somewhat ugly). You create a ctype facet that classifies the desired delimiters as whitespace, create a locale containing that facet, then imbue the st...
What is the point of the diamond operator () in Java 7?
The diamond operator in java 7 allows code like the following:
7 Answers
7
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ActiveRecord.find(array_of_ids), preserving order
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The answer is for mysql only
There is a function in mysql called FIELD()
Here is how you could use it in .find():
>> ids = [100, 1, 6]
=> [100, 1, 6]
>> WordDocument.find(ids).collect(&:id)
=> [1, 6, 100]
>> WordDocument.find(ids, :order => "field(id,...
What exactly is a C pointer if not a memory address?
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The C standard does not define what a pointer is internally and how it works internally. This is intentional so as not to limit the number of platforms, where C can be implemented as a compiled or interpreted language.
A pointer value can be some kind of ID or handle or a combin...
Which Python memory profiler is recommended? [closed]
I want to know the memory usage of my Python application and specifically want to know what code blocks/portions or objects are consuming most memory.
Google search shows a commercial one is Python Memory Validator (Windows only).
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How to delete a remote tag?
...r a branch and for a tag. If you want to make sure that you cannot accidentally remove the branch instead of the tag, you can specify full ref which will never delete a branch:
git push origin :refs/tags/tagname
If you also need to delete the local tag, use:
git tag --delete tagname
Background
Pu...
How to organize large R programs?
...l as a means for namespaces.
Just running source() over code works for really short snippets. Everything else should be in a package -- even if you do not plan to publish it as you can write internal packages for internal repositories.
As for the 'how to edit' part, the R Internals manual has ex...