If you are using HSQL (for free apps), there is a built in database viewer. In the Modeler, go to the Console tab, select Advanced and then Start Built-In Database viewer.
For other databases, you'll need to use tools for each database (for instance PgAdmin for Postgres).
Hope that helps,
If you want you can check it out with postgres, see: https://docs.mendix.com/developerportal/operate/restore-backup-locally
Are you looking to see database tables? If so you can open built in database viewer from Desktop Modeler Console -> Advanced. Options are enabled when you run your app locally
The database view is just enable, when the project is locally deployed.
How can I see the database on production cloud server?
Go to your app, navigate to Backups, select the environment you want, and then either create or just download one of the existing backups with database only.
Then see Maarten's post above for info how to restore it to PGadmin.
Hope this helps
Actually, the question doesn`t relates to backup database. I need to upload a big data to my application database on production cloud. I mean, how can I open the database like in sql viewer and add this data using sql queries?
Sorry from me, could you please explain how can you re-upload it? I don`t see a possibility to upload a snapshot to the project.