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Difference between a theta join, equijoin and natural join
I'm having trouble understanding relational algebra when it comes to theta joins, equijoins and natural joins. Could someone please help me better understand it? If I use the = sign on a theta join is it exactly the same as just using a natural join?
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Custom views with Storyboard
... UIView and the MyWidget class is the File Owner of the UIView. In the init of this widget I do a loadNibNamed .
3 Answe...
How to determine whether a Pandas Column contains a particular value
... entry in a Pandas column that has a particular value. I tried to do this with if x in df['id'] . I thought this was working, except when I fed it a value that I knew was not in the column 43 in df['id'] it still returned True . When I subset to a data frame only containing entries matching the ...
How to implement a secure REST API with node.js
I start planning a REST API with node.js ,express and mongodb. The API provides data for a website (public and private area) and maybe later a mobile app. The frontend will be developed with AngularJS.
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What's the most elegant way to cap a number to a segment? [closed]
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The way you do it is pretty standard. You can define a utility clamp function:
/**
* Returns a number whose value is limited to the given range.
*
* Example: limit the output of this computation to between 0 and 255
* (x * 255).clamp(...
Finding quaternion representing the rotation from one vector to another
...follow
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edited Jul 11 '17 at 1:44
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answered Jul 23 '09 at 1...
What is the difference between synchronous and asynchronous programming (in node.js)
...m will block in the first line. The next line (console.log) will have to wait.
In the second example, the console.log will be executed WHILE the query is being processed. That is, the query will be processed in the background, while your program is doing other things, and once the query data is rea...
Is there a SASS.js? Something like LESS.js?
I have used LESS.js before. It's easy to use, something like
7 Answers
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Why does the JVM still not support tail-call optimization?
...ains why the JVM does not support tail-call optimization.
But although it is well known how to automatically transform a tail-recursive function into a simple loop, the Java specification doesn't require that this transformation be made. Presumably, one reason it is not a requirement is that, in...
How can I change the color of my prompt in zsh (different from normal text)?
... output on a commandline, I want to change the color of my prompt, so that it is visibly different from the programs output. As I use zsh, can anyone give me a hint?
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