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What is the difference between “INNER JOIN” and “OUTER JOIN”?
...ables, with a single column each, and data as follows:
A B
- -
1 3
2 4
3 5
4 6
Note that (1,2) are unique to A, (3,4) are common, and (5,6) are unique to B.
Inner join
An inner join using either of the equivalent queries gives the intersection of the two tables, i.e. the two r...
Loop through an array in JavaScript
...e seen this anti-pattern so many times.
Anti-pattern:
const numbers = [1,2,3,4,5], doubled = [];
numbers.forEach((n, i) => { doubled[i] = n * 2 });
Proper use case of map:
const numbers = [1,2,3,4,5];
const doubled = numbers.map(n => n * 2);
console.log(doubled);
Also, if you are ...
How to calculate time in hours between two dates in iOS
...weenDates = [date1 timeIntervalSinceDate:date2];
double secondsInAnHour = 3600;
NSInteger hoursBetweenDates = distanceBetweenDates / secondsInAnHour;
See, the apple reference library http://developer.apple.com/library/mac/navigation/
or if you are using Xcode just select help/documentation from ...
How to make graphics with transparent background in R using ggplot2?
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How do you search for files containing DOS line endings (CRLF) with grep on Linux?
...6
pjzpjz
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How to change the font on the TextView?
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343
First, the default is not Arial. The default is Droid Sans.
Second, to change to a different ...
Is gcc std::unordered_map implementation slow? If so - why?
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What is the difference between Nexus and Maven?
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“simple” vs “current” push.default in git for decentralized workflow
...).
– void.pointer
Jan 14 '15 at 16:23
7
Simple seems the safer "seat belt" option.
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Allow multiple roles to access controller action
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edited Jan 3 at 15:03
Sonhja
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