/**
* @return Instance of Database class.
*/
public static function getInstance()
{
if (Database::$INSTANCE == null) {
Database::$INSTANCE = new Database();
}
return Database::$INSTANCE;
}
$db_host = "localhost";
$db_user = "username";
$db_password = "password";
$db_name = "database_name";
$db = new mysqli($db_host, $db_user, $db_password, $db_name);
if ($db->connect_error) {
die("Connection failed: " . $db->connect_error);
}
// Query the database
$result = $db->query("SELECT * FROM table_name");
// Fetch data
while ($row = $result->fetch_assoc()) {
echo $row['column_name'];
}
// Close the database connection
$db->close();
$db_host = "localhost";
$db_user = "username";
$db_password = "password";
$db_name = "database_name";
$db = new PDO("pgsql:host=$db_host;dbname=$db_name", $db_user, $db_password);
// Insert data into table
$stmt = $db->prepare("INSERT INTO table_name (column1, column2) VALUES (:value1, :value2)");
$stmt->bindParam(':value1', $value1);
$stmt->bindParam(':value2', $value2);
$value1 = "example";
$value2 = "data";
$stmt->execute();
// Close the database connection
$db = null;
In this example, we're using the PDO package to connect to a PostgreSQL database and insert data into a table. We're using prepared statements to prevent SQL injection attacks.
Both of these examples use different package libraries - mysqli and PDO, respectively - which are built-in PHP libraries for connecting to and interacting with databases. /**
* @return Instance of Database class.
*/
public static function getInstance()
{
if (Database::$INSTANCE == null) {
Database::$INSTANCE = new Database();
}
return Database::$INSTANCE;
}
