Local Wordpress second database access

[peterk]

Just installed XAMPP 8.4.2-4 on MacOS Sonoma to locally test website stuff.
Everything starts up fine. Wordpress install works fine.

I use a second MYSQL database (in addition to the wordpress DB) which some of my pages use to generate page content using PHP. This works fine on my internet provider’s server but on my local install no output is generated.

In can use Sequel to open and edit this second database on my local install.

How can I troubleshoot this? Where and how could I log potential errors from MYSQL?
Is there a permission issue, since wordpress is trying to access a database it didn’t create?

Thanks

[peterk]

Partially answering my own questions:
Activate WP_DEBUG flags in wp-config.php.

Use correct password for MYSQL DB (or no password).