CiviCRM Initalization Error: DB Error: extension not found

Question

I've got CiviCRM installed within a WordPress context, and both are updated. The problem is that, with the last update that occurred, I can no longer get to CiviCRM. Instead, I get the following displayed on a blank page without any styling:

Initialization Error

Array
(
    [callback] => Array
        (
            [0] => CRM_Core_Error
            [1] => simpleHandler
        )

    [code] => -25
    [message] => DB Error: extension not found
    [mode] => 16
    [debug_info] =>  [DB Error: extension not found]
    [type] => DB_Error
    [user_info] =>  [DB Error: extension not found]
    [to_string] => [db_error: message="DB Error: extension not found" code=-25 mode=callback callback=CRM_Core_Error::simpleHandler prefix="" info=" [DB Error: extension not found]"]
)

Does anyone have any idea how I can fix this? It says an extension is not found, but there is no mention of what the extension is or why it's missing as the result of an update.

Answer 1

This turned out to be the issue with PEAR trying to load DB (mysql) extension. PHP mysql extension is removed from PHP7.

For those who landed here with same errors, when trying to execute commands with civix or drush which uses command-line php (php-cli), if your OS has installed both PHP5 and PHP7, the default php command available in /usr/bin/php refers to PHP7 while PHP5 executable will be available as /usr/bin/php5

One needs to update /usr/bin/php to /usr/bin/php7 and direct /usr/bin/php5 towards /usr/bin/php. Maybe using update-alternatives would be best suited.

Answer 2

I was facing the same error. I solved it by changing mysql: to mysqli: in civicrm.settings.php file. Reference - https://issues.civicrm.org/jira/browse/CRM-17874

Thanks.