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Database Structure for Tree Data Structure
...o-nested-sets
There are other models as well, including materialized path and nested sets:
http://communities.bmc.com/communities/docs/DOC-9902
Joe Celko has written a book on this subject, which is a good reference from a general SQL perspective (it is mentioned in the nested set article link abo...
Split column at delimiter in data frame [duplicate]
... rename it appropriately (the rename function from the reshape package is handy for doing this on the fly) and then rbind it with the existing data frame -- extra effort to get it inserted in place of the previous single column rather than as the first or last columns ...
– Ben...
Why is early return slower than else?
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This is a pure guess, and I haven't figured out an easy way to check whether it is right, but I have a theory for you.
I tried your code and get the same of results, without_else() is repeatedly slightly slower than with_else():
>>> T(l...
How to remove a web site from google analytics
...eb property that you want to delete from the dropdown.
In the right-hand column, click on "View Settings." ("Property Settings" in dec. 2015)
At the bottom of the next page, select "Delete this view."
It will warn you that you're about to delete all of the data associated with th...
Javascript: get package.json data in gulpfile.js
...thin the gulpfile.js; For instance, I want to get the homepage or the name and use it in a task.
4 Answers
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iphone/ipad: How exactly use NSAttributedString?
Yes, many people are saying about Rich Text in iPhone/iPad and many knows about NSAttributedString .
9 Answers
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How to create a WPF Window without a border that can be resized via a grip only?
...indow (even without setting any transparency values) the border disappears and you can only resize via the grip.
<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Width="640" Height="480"
WindowStyle=...
Python if-else short-hand [duplicate]
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The most readable way is
x = 10 if a > b else 11
but you can use and and or, too:
x = a > b and 10 or 11
The "Zen of Python" says that "readability counts", though, so go for the first way.
Also, the and-or trick will fail if you put a variable instead of 10 and it evaluates to Fals...
Swift and mutating struct
There is something that I don't entirely understand when it comes to mutating value types in Swift.
7 Answers
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Best practices for exception management in Java or C# [closed]
I'm stuck deciding how to handle exceptions in my application.
15 Answers
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