It is possible to connect a database on several websites?

Describe your issue a little bit more.

I would like to be able to connect the same database on two different sites

Intern and extern site?

If so, to connect an intern site with a DB is not the problem, you can use wix-data.
But if you want to connect a DB which is on another site (outside of your site-project) you will need to generate an endpoint and fetch the data from your endpoint.

An example for generating an ENDPOINT you will find here…
https://www.wix.com/velo/forum/coding-with-velo/creating-a-http-endpoint

How to fetch you will find here…
https://www.wix.com/velo/reference/wix-fetch

Hi Méliau,
There is no non-coding solution to use a database between two of your sites. You can submit a feature request for this through Wix Customer Care . Thanks for your question!

Expose your DB from site A and fetch on site B. Totally possible WITH code.