Use the PHP OCI8 extension to access Oracle Database.
Documentation is at https://www.php.net/oci8
Use pecl install oci8 to install for PHP 8.2 and PHP 8.3.
Use pecl install oci8-3.2.1 to install for PHP 8.1.
Use pecl install oci8-3.0.1 to install for PHP 8.0.
Use pecl install oci8-2.2.0 to install for PHP 7.
If your PHP was built with DTrace enabled, then set the environment variable
PHP_DTRACE=yes before running pecl install oci8. For example, on Linux:
export PHP_DTRACE=yes
You may additionally need the dtrace-devel or systemtap-sdt-devel package installed.
The PHP OCI8 extension can be linked with Oracle client libraries from Oracle Database 11.2 or later. These libraries are found in your database installation, or in the free Oracle Instant Client from
https://www.oracle.com/database/technologies/instant-client.html
Install the 'Basic' or 'Basic Light' Instant Client package. If building from source, then also install the SDK package.
Oracle Database's standard cross-version connectivity applies. For example, PHP OCI8 linked with Instant Client 19c can connect to Oracle Database 11.2 or later. See Oracle Support's note "Oracle Client / Server Interoperability Support" (ID 207303.1) for details.
A sample configuration php.ini file is at https://github.com/php/pecl-database-oci8/blob/main/oci8.ini
From PHP 8.4 the source code for PHP OCI8 is at: https://github.com/php/pecl-database-oci8/
For earlier versions, see the PHP source, e.g.: https://github.com/php/php-src/tree/PHP-8.3/ext/oci8