Spread your database connections with PHP PDO
Less is more
To retrieve data from the MySQL database, in a PHP script
retrieveMySQLData_PDO.php, create a connection with the MySQL database using the PDO constructor. Prepare an SQL statement to run an SQL query using the
prepare() function. Parameter markers may be used in a prepared statement. Specify a parameter marker for the CATALOGID column.
$stmt = $connection->prepare("SELECT * from CATALOG WHERE CATALOGID=?");
Set the cursor to be scrollable for the result set returned by the SQL query using the
$stmt ->setAttribute(PDO::ATTR_CURSOR, PDO::CURSOR_SCROLL);
Bind a PHP variable for the
catalogId value to the parameter marker using the
$catalogId='catalog1'; $stmt->bindParam(1, $catalogId);
Run the prepared statement using the
Retrieve a row of data from the result set using the
fetch() function. Iterate over the result set and add the data retrieved to the HTML table.
We shall use the
oci PDO driver to connect with the Oracle database. Create a PHP script,
createOracleTable_PDO.php. Create a connection with the Oracle database using the PDO constructor. The only difference from obtaining a connection with MySQL database is that the
oci PDO driver is used instead of the
mysql PDO driver.
$db = "oci:dbname=ORCL;host=localhost;port=1521"; $connection = new PDO($db, $user, $password);
Similar to the MySQL, database run SQL statements to create a database table, add data to the database table and retrieve data from the table. The
query() function may be used to run an SQL query instead of a prepared statement.
IBM DB2 9 Trial Version
We shall use the
odbc driver for PDO to connect with the DB2 database. Create a PHP script
retrieveDB2Table_PDO.php. Create a connection with the DB2 database using the PDO constructor and the ODBC driver.
$connection = new PDO('odbc:SAMPLE', $user, $password);
The procedure to create a database table, and for adding data to and for retrieving data from the table is the same as MySQL and Oracle. The advantage of the PDO class library is that PHP scripts that may be run with any database by just modifying the connection parameters for the database specific PDO driver in the PDO constructor.
SQL Server 2005 Express Edition
We shall use the SQL Server PDO driver to connect with the SQL Server database. Create a PHP script
createSQLServerTable_PDO.php. Obtain a connection with the SQL Server database using the PDO constructor and the
mssql driver for SQL Server. The hostname and
port are specified in
host parameter in format
$connection=new PDO ('mssql:host=localhost,2107;dbname=tempdb', $user, $password);
The procedure to create a database table, add data to the database table, and retrieve data is the same as for the other databases.
In this article you learned to connect to different databases with the PHP PDO drivers using the same set of PHP functions. The same PHP scripts may be used by just modifying the connection parameters.®