Ability to create a connection without database name (cross-database query)

[storm1er]

Is your feature request related to a problem? Please describe.
Explicit title: As we can't create a connection without a database name, we can't execute cross-database query

Use case: I have 20 databases on the same MySQL server. There's no workaround to run the same query 20 times, the only way is to create a connection for each database even if it's on the same server.

Describe the solution you'd like

• Ability to create a connection without giving a database name
• Ability to run a request without a given database name

Describe alternatives you've considered
No workaround is available for now except running the cross-database request using another software

[gjsjohnmurray]

Related to #727

[gjsjohnmurray]

When you connect to your MySQL server does the tree show all 20 databases, with the one you named in the connection being first, followed by the other 19 in alpha order?

When you run a SELECT in which you prefix the table name(s) with databasename. do you get the data from the expected place?

[storm1er]

For now the workaround has been to create a connection using "mysql" as database name (config database) ... I'm able to see all databases afterwards