PHP PDO is a database access layer that provides a uniform interface for working with multiple databases.
PDO simplifies the common database operations including:
- Creating database connections
- Executing queries using prepared statements
- Calling stored procedures
- Performing transactions
- And handling errors
PDO allows you to work with any database that has a PDO driver available. PDO relies on database-specific drivers, e.g., PDO_MYSQL for MySQL, PDO_PGSQL for PostgreSQL, PDO_OCI for Oracle database, etc., to function properly. Here’s the complete list of PDO drivers.
Therefore, to use PDO for a specific database, you need to have a corresponding database driver available.
The following diagram illustrates how PDO works:
PDO makes it easy to deploy PHP applications because it doesn’t require you to manually include any script files in your application like other libraries.
Section 1. PDO Quick Start #
This section shows you step by step how to connect to some relational database management systems, including MySQL and PostgreSQL.
- Connect to MySQL – show you step-by-step on how to connect to the MySQL database.
- Connect to PostgreSQL – show you how to connect to the PostgreSQL database.
Section 2. Creating a sample database #
- Create a sample database – show you how to create a sample database and tables in the MySQL database server and a reusable script for connecting to the database.
- Creating new tables – learn how to create a new table in a MySQL database from PHP using PDO.
Section 3. Prepared Statements #
- Prepared statement – introduce to you the prepared statement.
- Execute the LIKE operator – show you how to use a prepare statement to execute a query that contains the LIKE operator.
- Execute the IN operator – learn how to use a prepared statement to execute a query that contains the IN operator.
Section 4. CRUD in PDO #
This section illustrates the common database operation, including creating (insert), reading(select), updating, and deleting data using PDO. These basic operations are often called CRUD.
- Inserting data into a table – walk you through the steps of inserting data into a table of a database.
- Updating data in a table – show you how to update data in a table from PHP using PDO.
- Selecting data from a table – guide you on how to query data from a table.
- Deleting data from a table – show you how to delete data in the database table using PDO API.
Section 5. Fetching data #
This section discusses various fetch* methods and modes in detail.
- fetch() – fetch a row from a result set associated with a PDOStatement object.
- fetchAll() – fetch all rows from a result set object into an array.
- fetchcolumn() – fetch a single column from the next row in a result set.
- fetchObject() – fetch the next row from a result set and returns it as an object of a class.
- PDO::FETCH_KEY_PAIR – select a two-column result in an array where the first column is the key and the second column is the value
- PDO::FETCH_GROUP – group rows by the unique values of the first column in the result set.
- PDO::FETCH_CLASS – show you how to return an instance of a class whose properties map to the column values from the database.
Section 6. Calling Stored Procedures #
This section shows you some examples of dealing with stored procedures, including:
- Calling a MySQL stored procedure from PHP using PDO – show you how to call a MySQL stored procedure from PHP using PDO.
Section 6. Managing Transaction in PDO #
PDO provides you with some handy methods, including beginTransaction(), commit() and rollBack() that handles transactions effectively. This section gives you some examples of handling transactions in your web application.
- PDO Transaction – learn how to perform a database transaction from PHP using PDO.
Section 7. PDO References #
- http://www.php.net/manual/en/book.pdo.php – PHP Data Objects
