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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 ...
Are PHP functions case sensitive?
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edited Dec 29 '14 at 23:03
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answered Apr 13 '11 at 1:41
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Is gcc std::unordered_map implementation slow? If so - why?
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Rename Pandas DataFrame Index
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243
The rename method takes a dictionary for the index which applies to index values.
You want to re...
View all TODO items in Visual Studio using GhostDoc
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How to export query result to csv in Oracle SQL Developer?
I'm using Oracle SQL Developer 3.0. Trying to figure out how to export a query result to a text file (preferably CSV). Right clicking on the query results window doesn't give me any export options.
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What is the way to quick-switch between tabs in Xcode 4
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Ben Clayton
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answered Jun 27 '11 at 9:43
gsempegsempe...
How can I initialize a C# List in the same line I declare it. (IEnumerable string Collection Example
...ially the syntax is:
new List<Type> { Instance1, Instance2, Instance3 };
Which is translated by the compiler as
List<string> list = new List<string>();
list.Add("One");
list.Add("Two");
list.Add("Three");
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