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Remove empty array elements
...e removed. So if you need to preserve elements that are i.e. exact string '0', you will need a custom callback:
// PHP 7.4 and later
print_r(array_filter($linksArray, fn($value) => !is_null($value) && $value !== ''));
// PHP 5.3 and later
print_r(array_filter($linksArray, function($valu...
UITableViewCell subview disappears when cell is selected
...enting a color-chooser table view where the user can select amongst, say, 10 colors (depends on the product). The user can also select other options (like hard drive capacity, ...).
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HashSet versus Dictionary w.r.t searching time to find if an item exists
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HashSet vs List vs Dictionary performance test, taken from here.
Add 1000000 objects (without checking duplicates)
Contains check for half the objects of a collection of 10000
Remove half the objects of a collection of 10000
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php check if array contains all array values from another array
... Chris
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answered Mar 11 '12 at 14:21
jasonbarjasonbar
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MySQL: Insert record if not exists in table
...tnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;
Query OK, 1 row affected (0.00 sec)
Records: 1 Duplicates: 0 Warnings: 0
SELECT * FROM `table_listnames`;
+----+------...
comparing 2 strings alphabetically for sorting purposes
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edited Dec 10 '14 at 18:15
answered Apr 17 '12 at 20:05
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Node.js client for a socket.io server
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answered May 22 '12 at 14:05
alessioalexalessioalex
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How to find the size of an array in postgresql
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Adam DingleAdam Dingle
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10
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Is there a REAL performance difference between INT and VARCHAR primary keys?
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Tamlyn
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answered Dec 1 '08 at 21:47
Bill KarwinBill Karwin
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Difference between Django's annotate and aggregate methods?
...gt; q = Book.objects.annotate(num_authors=Count('authors'))
>>> q[0].num_authors
2
>>> q[1].num_authors
1
q is the queryset of books, but each book has been annotated with the number of authors.
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