Build a PHP application that uses YSQL

The following tutorial shows a small PHP application that connects to a YugabyteDB cluster using the php-pgsql driver and performs basic SQL operations. Use the application as a template to get started with YugabyteDB Aeon in PHP.

Prerequisites

• PHP runtime. The sample application was created using PHP 8.1 but should work with earlier and later versions. Homebrew users on macOS can install PHP using brew install php.
• php-pgsql driver.
  • On macOS, Homebrew automatically installs the driver with brew install php.
  • Ubuntu users can install the driver using the sudo apt-get install php-pgsql command.
  • CentOS users can install the driver using the sudo yum install php-pgsql command.

Clone the application from GitHub

Clone the sample application to your computer:

git clone https://github.com/YugabyteDB-Samples/yugabyte-simple-php-app.git && cd yugabyte-simple-php-app

Provide connection parameters

If your cluster is running on YugabyteDB Aeon, you need to modify the connection parameters so that the application can establish a connection to the YugabyteDB cluster. (You can skip this step if your cluster is running locally and listening on 127.0.0.1:5433.)

To do this:

1. Open the sample-app.php file.

2. Set the following configuration-related constants:

   • HOST - the host name of your YugabyteDB cluster. For local clusters, use the default (127.0.0.1). For YugabyteDB Aeon, select your cluster on the Clusters page, and click Settings. The host is displayed under Connection Parameters.
   • PORT - the port number for the driver to use (the default YugabyteDB YSQL port is 5433).
   • DB_NAME - the name of the database to connect to (the default is yugabyte).
   • USER and PASSWORD - the username and password for the YugabyteDB database. For local clusters, use the defaults (yugabyte and yugabyte). For YugabyteDB Aeon, use the credentials in the credentials file you downloaded.
   • SSL_MODE - the SSL mode to use. YugabyteDB Aeon requires SSL connections; use verify-full.
   • SSL_ROOT_CERT - the full path to the YugabyteDB Aeon cluster CA certificate.

3. Save the file.

Run the application

Run the application.

$ php sample-app.php

You should see output similar to the following:

>>>> Successfully connected to YugabyteDB!
>>>> Successfully created table DemoAccount.
>>>> Selecting accounts:
name = Jessica, age = 28, country = USA, balance = 10000
name = John, age = 28, country = Canada, balance = 9000
>>>> Transferred 800 between accounts.
>>>> Selecting accounts:
name = Jessica, age = 28, country = USA, balance = 9200
name = John, age = 28, country = Canada, balance = 9800

You have successfully executed a basic PHP application that works with YugabyteDB Aeon.

Explore the application logic

Open the sample-app.php file in the yugabyte-simple-php-app folder to review the methods.

connect

The connect method establishes a connection with your cluster via the php-pgsql driver.

$conn = new PDO('pgsql:host=' . HOST . ';port=' . PORT . ';dbname=' . DB_NAME .
                ';sslmode=' . SSL_MODE . ';sslrootcert=' . SSL_ROOT_CERT,
                USER, PASSWORD,
                array(PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
                        PDO::ATTR_EMULATE_PREPARES => true,
                        PDO::ATTR_PERSISTENT => true));

create_database

The create_database method uses PostgreSQL-compliant DDL commands to create a sample database.

$conn->exec('DROP TABLE IF EXISTS DemoAccount');

$conn->exec('CREATE TABLE DemoAccount (
                id int PRIMARY KEY,
                name varchar,
                age int,
                country varchar,
                balance int)');

$conn->exec("INSERT INTO DemoAccount VALUES
                (1, 'Jessica', 28, 'USA', 10000),
                (2, 'John', 28, 'Canada', 9000)");

select_accounts

The select_accounts method queries your distributed data using the SQL SELECT statement.

$query = 'SELECT name, age, country, balance FROM DemoAccount';

foreach ($conn->query($query) as $row) {
    print 'name=' . $row['name'] . ', age=' . $row['age'] . ', country=' . $row['country'] . ', balance=' . $row['balance'] . "\n";
}

transfer_money_between_accounts

The transfer_money_between_accounts method updates your data consistently with distributed transactions.

try {
    $conn->beginTransaction();
    $conn->exec("UPDATE DemoAccount SET balance = balance - " . $amount . " WHERE name = 'Jessica'");
    $conn->exec("UPDATE DemoAccount SET balance = balance + " . $amount . " WHERE name = 'John'");
    $conn->commit();
    print ">>>> Transferred " . $amount . " between accounts\n";
} catch (PDOException $e) {
    if ($e->getCode() == '40001') {
        print "The operation is aborted due to a concurrent transaction that is modifying the same set of rows.
                Consider adding retry logic for production-grade applications.\n";
    }

    throw $e;
}

Learn more

php-pgsql driver