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SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?
... cross join produces a cartesian product between the two tables, returning all possible combinations of all rows. It has no on clause because you're just joining everything to everything.
A full outer join is a combination of a left outer and right outer join. It returns all rows in both tables t...
Android emulator and virtualbox cannot run at same time
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Thanks @MichaelHampton. I installed vagrant-libvert and it worked!
– jchook
Jan 13 '19 at 21:42
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difference between fork and branch on github
If I fork a project that's hosted on github. Do I fork all the branches? How do I know which branch my fork is based on? In other words which branch will be downloaded to my PC?
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How to sign an android apk file
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https://developer.android.com/studio/publish/app-signing.html
Okay, a small overview without reference or eclipse around, so leave some space for errors, but it works like this
Open your project in eclipse
Press right-mouse - > tools (android tools?) - > export signed application (apk?)
G...
Uninstall / remove a Homebrew package including all its dependencies
I have a Homebrew formula that I wish to uninstall/remove along with all its dependencies, skipping packages whom other packages depend upon (a.k.a. Cascading package removal in Package manager parlance).
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how do I make a single legend for many subplots with matplotlib?
... multiple subplots with matplotlib. That is, I have 9 plots on a 3x3 grid, all with the same for lines (of course, different values per line).
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How to get RGB values from UIColor?
...rView.backgroundColor;//line 2
CGColorRef colorRef = [color CGColor];
int _countComponents = CGColorGetNumberOfComponents(colorRef);
if (_countComponents == 4) {
const CGFloat *_components = CGColorGetComponents(colorRef);
CGFloat red = _components[0];
CGFloat green = _components[1...
Why use Ruby's attr_accessor, attr_reader and attr_writer?
...write classes which will work correctly no matter how their public API is called.
class Person
attr_accessor :age
...
end
Here, I can see that I may both read and write the age.
class Person
attr_reader :age
...
end
Here, I can see that I may only read the age. Imagine that it is set ...
Zip lists in Python
...x. list, string, tuple, dictionary)
Output (list)
1st tuple = (element_1 of numbers, element_1 of letters)
2nd tuple = (e_2 numbers, e_2 letters)
…
n-th tuple = (e_n numbers, e_n letters)
List of n tuples: n is the length of the shortest argument (input)
len(numbers) =...
Multiple aggregations of the same column using pandas GroupBy.agg()
... functions f1, f2 to the same column df["returns"] , without having to call agg() multiple times?
3 Answers
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