(PHP 5, PECL OCI8 >= 1.1.0)
oci_server_version — Returns the Oracle Database version
$connection
   )Returns a string with the Oracle Database version and available options
connection
   Returns the version information as a string or FALSE on error.
  
Example #1 oci_server_version() example
<?php
    $conn = oci_connect("scott", "tiger");
    echo "Server Version: " . oci_server_version($conn);
    // Displays:
    // Server Version: Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
    // With the Partitioning, OLAP, Data Mining and Real Application Testing option
    oci_close($conn);
?>
Note:
In PHP versions before 5.0.0 you must use ociserverversion() instead. This old name still can be used. However it is deprecated and not recommended.