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What is the best collation to use for MySQL with PHP? [closed]
... ? are you sure about this ? publib.boulder.ibm.com/infocenter/db2luw/v9r5/index.jsp?topic=/… The collation you choose can significantly impact the performance of queries in the database.
– Adam Ramadhan
Aug 7 '10 at 7:54
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List of Big-O for PHP functions
...nd
array_pop/array_push is faster than array_shift/array_unshift due to re-index penalty
Lookups:
array_key_exists O(n) but really close to O(1) - this is because of linear polling in collisions, but because the chance of collisions is very small, the coefficient is also very small. I find you tr...
Laravel migration: unique key is too long, even if specified
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You have to set the length of the indexed column according to the limit of 767 bytes. Be aware that VARCHAR may have 1, 2 or 4 bytes for each length unit. Example: utf8_mb4 (4 bytes) -> 767 / 4 = 191. Otherwise utf8_general_ci for VARCHAR(X) with X < 85...
What's the difference between echo, print, and print_r in PHP?
..._3=array(99,98,97) // Arrays are not possible with echo (loop or index value required)
$var_4=array("P"=>"3","J"=>"4"); // Arrays are not possible with echo (loop or index value required)
You can also use echo statement with or without parenthese
echo ("Hello World"); // thi...
MongoDB sort排序、index索引教程 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
MongoDB sort排序、index索引教程MongoDB sort()排序方法在MongoDB中使用使用sort()方法对数据进行排序，sort()方法可以通过参数指定排序的字段，并使用 1 和 -1 来指...MongoDB sort排序
在MongoDB中使用使用sort()方法对数据进行排序，sort()方法...
How to insert element into arrays at specific position?
...Also, using array_merge as TMS suggested won't require you to use a unique index. EXAMPLE: Add "new-value" to an existing array: $b = array_merge( array_slice( $a, 0, 1, true ), array( 'new-value' ), array_slice( $a, 1, null, true ) );
– Radley Sustaire
Jun 20 ...
upstream sent too big header while reading response header from upstream
...h logged lines preceding the message? PHP message: PHP Notice: Undefined index:
Example snippet from a loop my log file:
2015/11/23 10:30:02 [error] 32451#0: *580927 FastCGI sent in stderr: "PHP message: PHP Notice: Undefined index: Firstname in /srv/www/classes/data_convert.php on line 1090
PHP...
How do I get a file name from a full path with PHP?
...ame.
The example from the PHP manual:
<?php
$path = "/home/httpd/html/index.php";
$file = basename($path); // $file is set to "index.php"
$file = basename($path, ".php"); // $file is set to "index"
?>
share
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Create subdomains on the fly with .htaccess (PHP)
...riteEngine on
RewriteCond %{HTTP_HOST} ^[^.]+\.example\.com$
RewriteRule !^index\.php$ index.php [L]
Inside the index.php you can than extract the subdomain using:
if (preg_match('/^([^.]+)\.example\.com$/', $_SERVER['HTTP_HOST'], $match)) {
var_dump($match[1]);
}
But all this requires that...
How to avoid isset() and empty()
...t write a function for that. Something like:
function get_string($array, $index, $default = null) {
if (isset($array[$index]) && strlen($value = trim($array[$index])) > 0) {
return get_magic_quotes_gpc() ? stripslashes($value) : $value;
} else {
return $default;
...