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Is it better to use Enumerable.Empty() as opposed to new List() to initialize an IEnumerable
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Yes. Enumerable<>.Empty does avoid allocating a new object, which is a small bonus.
– Neil
Jan 4 '10 at 18:38
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What does PHP keyword 'var' do?
...'t been able to find the answer neither through web search engines, nor on php.net. Please just direct me to where I can read about this, if you haven't got time to explain.
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Is there a way to use shell_exec without waiting for the command to complete?
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How about adding.
"> /dev/null 2>/dev/null &"
shell_exec('php measurePerformance.php 47 844 email@yahoo.com > /dev/null 2>/dev/null &');
Note this also gets rid of the stdio and stderr.
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Why is the Android emulator so slow? How can we speed up the Android emulator? [closed]
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I got "Failed to allocate memory" when setting 1024. It also displayed a warning at the bottom of the configuration window saying: "On Windows, emulating RAM greater than 768M may fail dependin..." I Tried setting it to 770, and then it worke...
PHP/MySQL insert row then get 'id'
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The PDO equivalent is PDO::lastInsertId (us3.php.net/manual/en/pdo.lastinsertid.php).
– Matthew Flaschen
May 22 '09 at 11:18
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Hibernate, @SequenceGenerator and allocationSize
...eases real database sequence by one , multiple this value by 50 (default allocationSize value) - and then uses this value as entity ID.
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Under what circumstances are linked lists useful?
...any linked lists are stored in an array.
It avoids doing many small (de)allocations on inserts/deletes.
Initial loading of the hash table is pretty fast, because the array is filled sequentially (plays very nice with CPU cache).
Not to mention that a chaining hash table is expensive in terms of ...
What is stdClass in PHP?
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stdClass is PHP's generic empty class, kind of like Object in Java or object in Python (Edit: but not actually used as universal base class; thanks @Ciaran for pointing this out).
It is useful for anonymous objects, dynamic properties, ...
Create subdomains on the fly with .htaccess (PHP)
...s is done in the ServerAlias DOCs
Then extract and verify the subdomain in PHP and display the appropriate data
The long version
1. Create a wildcard DNS entry
In your DNS settings you need to create a wildcard domain entry such as *.example.org. A wildcard entry looks like this:
*.example.org....
PHP - Extracting a property from an array of objects
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If you have PHP 5.5 or later, the best way is to use the built in function array_column():
$idCats = array_column($cats, 'id');
But the son has to be an array or converted to an array
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