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MySQL Conditional Insert
..., try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = 123
AND item = 456)
In this, dual is a table with one row only (found originall...
How to get all possible combinations of a list’s elements?
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482
Have a look at itertools.combinations:
itertools.combinations(iterable, r)
Return r le...
What's the maximum value for an int in PHP?
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124
From the PHP manual:
The size of an integer is
platform-dependent, although a maximum
value of ...
Why can't code inside unit tests find bundle resources?
...est bundle.
– Chris
Jul 7 '12 at 15:47
1
@Chris In the sample line I'm assuming self refers to a ...
phonegap open link in browser
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edited Dec 4 '18 at 16:58
Erti-Chris Eelmaa
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Converting String to “Character” array in Java
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edited Jan 29 '14 at 22:45
David Newcomb
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Explain the use of a bit vector for determining if all characters are unique
...here are two differences between them:
Size. int has fixed size, usually 4 bytes which means 8*4=32 bits (flags). Bit vector usually can be of different size or you should specify the size in constructor.
API. With bit vectors you will have easier to read code, probably something like this:
vecto...
Determine the number of NA values in a column
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14 Answers
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Check if event exists on element [duplicate]
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144
$('body').click(function(){ alert('test' )})
var foo = $.data( $('body').get(0), 'events' ).cl...
What is the difference between URI, URL and URN? [duplicate]
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4 Answers
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