In web development, PHP is a very commonly used programming language. As an efficient database operation library, the PDO_SQLITE extension is also an important part of PHP. This article will introduce how to use the PDO_SQLITE extension in PHP.
Step One: Installation of PDO_SQLITE
Before using PDO_SQLITE, you first need to confirm whether it has been installed in your PHP environment. You can check by executing the following command:
php -m | grep pdo_sqlite
If the output result contains "pdo_sqlite", it means that the extension has been installed, otherwise it needs to be installed. In Linux systems, you can use the package manager to install PHP extensions. For example, in Debian/Ubuntu systems, you can use the following command:
sudo apt-get install php-pdo-sqlite
If using If it is a Windows system, you can edit the php.ini file and add the following extension:
extension=php_pdo_sqlite.dll
Note that the above command assumes that you are using PHP 5.x or 7.x Version. If other versions are installed, the command may need to be modified accordingly.
Step 2: Connect to SQLite database
Before performing database operations, you need to connect to the SQLite database first. You can use the PDO class to connect through the following code:
$db = new PDO('sqlite:/path/to/mydatabase.db');
Among them, /path/to/ mydatabase.db is the path to your local SQLite database.
It should be noted that a SQLite database can be created in PHP code in the following way:
try {
$db = new PDO("sqlite:mydatabase.db"); $db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); $db->exec("CREATE TABLE IF NOT EXISTS mytable (id INTEGER PRIMARY KEY, name TEXT, age INTEGER)");
} catch(PDOException $e) {
echo $e->getMessage();
}
The above code will create a SQLite database named mydatabase.db in the directory where the PHP script is located, and create a data table named mytable in it, which contains id, There are three columns: name and age.
Step 3: Execute SQL query
After the connection is successful, you can use the method provided by the PDO_SQLITE extension to execute the SQL query. For example:
$sql= "SELECT id, name, age FROM mytable";
$result = $db->query($sql);
At this time, $result Is a PDOStatement object, which contains all result sets that meet the query conditions. You can traverse and read the results through the fetch() method provided by PDOStatement.
while($row = $result->fetch(PDO::FETCH_ASSOC)) {
echo "ID: ".$row["id"].", Name: ".$row["name"].", Age: ".$row["age"]."
";
}
The above code will output each item in the mytable data table The ID, Name and Age of the row.
Step 4: Close the database connection
After using PDO_SQLITE, you can close the database connection through the following code:
$db = null;
You can also use the destructor of PDO_SQLITE to automatically close the connection:
unset($db);
Summary
PDO_SQLITE is a very useful PHP extension that can be easily Interact with SQLite databases in PHP scripts. Through the above introduction, I believe you have understood how to use the PDO_SQLITE extension to perform database operations. I hope it will be helpful to you.
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