How to do full text search and indexing using PHP and SQLite

How to use PHP and SQLite for full-text search and indexing

Introduction:
With the explosive growth of Internet information, full-text search has become one of the important means of processing massive data. When developing a website or application, we often need to implement full-text search functionality so that users can quickly find the information they need. This article will introduce in detail how to use PHP and SQLite to implement full-text search and indexing functions.

1. Install and configure SQLite

First, we need to install the SQLite database, which can be downloaded from its official website (https://www.sqlite.org/) for your system version and install it. After the installation is complete, the PHP extension for SQLite needs to be added to the PHP configuration file (php.ini) so that we can use the SQLite extension in PHP. Add the following content to the configuration file:

extension=sqlite3.so // for Linux
extension=php_sqlite3.dll // for Windows

Save the configuration file and restart the web server to Make sure the configuration takes effect.

2. Create SQLite database and data table

Before implementing full-text search and indexing, we first need to prepare a SQLite database and create a data table to store our data. Open a terminal or command prompt, go to your project directory, and execute the following command to create the database and data table:

sqlite3 mydatabase.db

CREATE TABLE articles (

id INTEGER PRIMARY KEY AUTOINCREMENT,
title TEXT,
content TEXT

);

Save and exit the SQLite terminal.

3. Insert data

We will simulate some article data and insert it into the database for full-text search and indexing. In PHP code, we can use the following code to insert data:

$pdo = new PDO("sqlite:mydatabase.db");
$pdo ->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$articles = [

['title' => '使用PHP进行全文搜索', 'content' => '在PHP中，我们有几种方法可以实现全文搜索功能。'],
['title' => 'PHP和SQLite全文搜索的厉害之处', 'content' => 'PHP和SQLite是一对绝佳的组合，它们可以轻松地实现全文搜索和索引功能。'],
// 更多文章...

];

foreach ($articles as $article) {

$sql = "INSERT INTO articles (title, content) VALUES (:title, :content)";
$stmt = $pdo->prepare($sql);
$stmt->execute($article);

}

?>

The above code will create a PDO instance to connect to the SQLite database and use prepared statements to insert data into the data table. You can insert more article data as needed.

4. Use full-text search and index

In SQLite, we can use FULL TEXT search and index to implement full-text search. First, we need to create a full-text index to speed up searches. We can create an index on the title and content columns of the article. Execute the following SQL statement to create the index:

CREATE VIRTUAL TABLE articles_fts USING FTS5(title, content);

Next, we need to copy the data in the original data table to the full-text index , and keep the index in sync with the original data. Execute the following SQL statement to achieve this:

INSERT INTO articles_fts(articles_fts) VALUES('rebuild');

This will keep the full-text index in sync with the original data. Next, we can use the following code to perform a full-text search:

$pdo = new PDO("sqlite:mydatabase.db");
$pdo- >setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$search = "PHP full text search";
$sql = "SELECT * FROM articles_fts WHERE content MATCH :search OR title MATCH : search";
$stmt = $pdo->prepare($sql);
$stmt->bindParam(':search', $search, PDO::PARAM_STR);
$stmt- >execute();

$results = $stmt->fetchAll(PDO::FETCH_ASSOC);

foreach ($results as $result) {

echo "标题：{$result['title']}，内容：{$result['content']}

";
}

?>

The above code will search for articles containing the keyword "PHP full text search" and output the results in the form of title and content.

Conclusion:
This article introduces how to use PHP and SQLite to implement full-text search and indexing functions. The implementation of full-text search can greatly improve the user experience of a website or application and help users quickly find the information they need. Through this In this way, we can easily implement full-text search and indexing functions in web applications that use SQLite as the database. I hope this article will be helpful to you!

The above is the detailed content of How to do full text search and indexing using PHP and SQLite. For more information, please follow other related articles on the PHP Chinese website!