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Difference between View and table in sql
...ns data, a view is just a SELECT statement which has been saved in the database (more or less, depending on your database).
The advantage of a view is that it can join data from several tables thus creating a new view of it. Say you have a database with salaries and you need to do some complex stat...
Extract elements of list at odd positions
... The result will contain the elements placed on the following positions (0-based, so first element is at position 0, second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2, 4, 6
Explanation
The [1::2] at the end is just a notation for list slicing. Usually it is in the following...
Which HTML elements can receive focus?
...
Here I have a CSS-selector based on bobince's answer to select any focusable HTML element:
a[href]:not([tabindex='-1']),
area[href]:not([tabindex='-1']),
input:not([disabled]):not([tabindex='-1']),
select:not([disabled]):not([tabindex='-1']),
...
reStructuredText tool support
...cessor) document.
rst2s5 - from reStructuredText to S5, a Simple Standards-based Slide Show System
rst2man - from reStructuredText to Man page
Haskell - Pandoc
Pandoc is a Haskell library for converting from one markup format to another, and a command-line tool that uses this library. It can read...
Is there a list of screen resolutions for all Android based phones and tablets? [closed]
... No I am not sure, a lot of these values were looked up from random databases on the interwebs and their results didn't always fill me with complete confidence.
– Oliver Pearmain
Jun 11 '14 at 11:40
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Create a Date with a set timezone without using a string representation
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@jishi—Date objects are based on a UTC time value, not local time. However, the default Date.prototype.toString method will display local time values.
– RobG
May 27 '13 at 5:54
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ActiveRecord.find(array_of_ids), preserving order
...ccording to the original list of IDs you used when looking up the record.
Based on the many excellent answers to Sort an array according to the elements of another array, I recommend the following solution:
Something.find(array_of_ids).sort_by{|thing| array_of_ids.index thing.id}
Or if you need ...
How do I convert a decimal to an int in C#?
...nd thus can be understood to be able to truncate even numbers that are not base 10, as opposed to Decimal.Truncate, which is a true truncation of a base 10 number.
– Brian
Jun 24 '09 at 20:55
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How do I escape ampersands in batch files?
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From a cmd:
& is escaped like this: ^& (based on @Wael Dalloul's answer)
% does not need to be escaped
An example:
start http://www.google.com/search?client=opera^&rls=en^&q=escape+ampersand%20and%20percentage+in+cmd^&sourceid=opera^&ie=utf-8^&am...
How to do exponentiation in clojure?
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You can use java's Math.pow or BigInteger.pow methods:
(Math/pow base exponent)
(.pow (bigint base) exponent)
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