Swoole and Workerman's optimization methods for index scanning and index coverage queries in PHP and MySQL

Swoole and Workerman's optimization methods for index scanning and index coverage queries in PHP and MySQL

Introduction:
In large-scale Web applications, database queries Performance optimization is crucial. Indexing is one of the most effective optimization methods that can speed up queries. For index scans and index coverage queries in PHP and MySQL, this article will introduce how to use Swoole and Workerman for optimization, and provide specific code examples.

1. Optimization method of index scan
Index scan is a way to satisfy query conditions by traversing the index tree. However, in large-scale data queries, the performance of index scans may be affected. In order to optimize index scanning, you can consider the following methods:

1. Use appropriate indexes: When designing a database table, you need to select appropriate index fields based on actual query requirements. Avoid invalid indexes and ensure the selectivity of indexed fields.
2. Avoid full table scan: For queries without index, it will lead to full table scan and affect query performance. You can avoid full table scans by adding indexes or optimizing query statements.
3. Use covering index: MySQL's covering index can directly obtain the data required for the query from the index, without the need to obtain data through table return operations. By using covering indexes, IO operations can be reduced and query performance improved.

The following is a sample code for using Swoole for index scan optimization:

use SwooleCoroutineMySQL;

$mysql = new MySQL() ;
$mysql->connect([

'host' => 'localhost',
'port' => 3306,
'user' => 'root',
'password' => 'password',
'database' => 'database',

]);

$mysql->set(['fetch_mode' => true]);

$users = $mysql->query("SELECT id, name FROM users WHERE age > 18");

foreach ($users as $user) {

echo "ID: " . $user['id'] . ", Name: " . $user['name'] . "

" ;
}

$mysql->close();
?>

2. Optimization method of index coverage query
Index coverage query refers to the query The required columns are included in the index, and there is no need to go back to the table to query. By using index coverage queries, you can reduce IO operations and improve query performance. Here are some methods to optimize index coverage queries:

1. Use Appropriate index: Same as index scan optimization, you need to select appropriate index fields according to actual query requirements. Make sure that the columns required for the query are included in the index.
2. Reduce the number of query columns: Try to query only the required ones Column, avoid querying unnecessary columns.
3. Avoid using SELECT : Use specific column names instead of SELECT , which can reduce the amount of data transmission.

The following is Sample code for index coverage query optimization using Workerman:

require_once DIR . '/vendor/autoload.php';

use WorkermanMySQLConnection ;

$mysql = new Connection('localhost', '3306', 'root', 'password', 'database');

$users = $mysql->select( 'id, name', 'users', ['age[>]' => 18]);

foreach ($users as $user) {

echo "ID: " . $user['id'] . ", Name: " . $user['name'] . "

";
}

$mysql->close();
?>

Conclusion:
Index scanning and indexing of PHP and MySQL through reasonable use of Swoole and Workerman Optimizing coverage queries can improve the performance of database queries. As can be seen from the code examples, methods such as appropriate index design, avoiding full table scans, and using index coverage queries are very important to improve the efficiency of database queries. I hope this article can help readers better optimize index scans and index coverage queries in PHP and MySQL.

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