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Difference between a theta join, equijoin and natural join
...e exact differences are fine, I want to show how the relational algebra is transformed to SQL and what the actual value of the 3 concepts is.
The key concept in your question is the idea of a join. To understand a join you need to understand a Cartesian Product (the example is based on SQL where t...
Simple logical operators in Bash
...meter expansion, expanding to the value of a variable, with possible extra transformations.
((…)) double parentheses surround an arithmetic instruction, that is, a computation on integers, with a syntax resembling other programming languages. This syntax is mostly used for assignments and in cond...
npm command to uninstall or prune unused packages in Node.js
...t;-- depends on c@~1.0.9
`-- c@1.0.10
In this case, npm-dedupe will transform the tree to:
a
+-- b
+-- d
`-- c@1.0.10
Because of the hierarchical nature of node's module lookup, b and d will both get their dependency met by the single c package at the root level of the tree.
The dedup...
How to pass json POST data to Web API method as an object?
...nience anyway - just take the content in as a string and use newtonsoft to transform it. Done. Took probably 30 seconds to solve it the "hard" way after trying for about an hour to solve it the "easy" way. I'm not wild about the approach, but is there a fundamental problem with it?
...
Booleans, conditional operators and autoboxing
...
The line:
Boolean b = true ? returnsNull() : false;
is internally transformed to:
Boolean b = true ? returnsNull().booleanValue() : false;
to perform the unboxing; thus: null.booleanValue() will yield a NPE
This is one of the major pitfalls when using autoboxing. This behavior is i...
Why do some C# lambda expressions compile to static methods?
...hanged this behavior. Now, any lambda, which captures variables or not, is transformed into a display class:
Given this example:
public class C
{
public void M()
{
var x = 5;
Action<int> action = y => Console.WriteLine(y);
}
}
Native compiler output:
public ...
Why is lazy evaluation useful?
...56
That's because lazy evaluation looks at the syntax tree and does tree-transformations...
square (square (square 2))
||
\/
*
/ \
\ /
square (square 2)
||
\/
*
/ \
\ /
*
...
How can I tell if a DOM element is visible in the current viewport?
...that the center of the element is visible if you have rounded corners or a transform applied, as the bounding corners may not return the expected element: element.contains(efp(rect.right - (rect.width / 2), rect.bottom - (rect.height / 2)))
– Jared
Mar 10 '15 a...
Finding three elements in an array whose sum is closest to a given number
...by representing each integer as a bit vector and performing a fast Fourier transform, but that's beyond the scope of this answer.
Note: Because this is an interview question, I've cheated a little bit here: this algorithm allows the selection of the same element multiple times. That is, (-1, -1, ...
Extending an Object in Javascript
I am currently transforming from Java to Javascript, and it's a bit hard for me to figure out how to extend objects the way I want it to do.
...