How can I connect to a MySQL database using Scala?

You can use JDBC - the standard means of getting Java to talk to databases. You'll need the appropriate MySQL JDBC driver. Apache DbUtils provides some utility classes surrounding JDBC and would be useful.

If you want a higher level API which takes some of the boilerplate out, then check out Spring's JDBC integration.

If you want an ORM (object-relational mapping), then Hibernate is a good choice.

I've used all three in Scala with success.

Off course you can use all Java version compatible with JDBC (Hibernate, Spring, etc), but for better use of Scala language, I recommend using a Scala specific framework, which have a better DSL.

• ScalaQuery is an API / DSL (domain specific language) built on top of JDBC for accessing relational databases in Scala. It was designed with the following goals in mind:
• Squeryl is a Scala ORM and DSL for talking with Databases with minimum verbosity and maximum type safety
• SORM is a Scala ORM-framework designed to eliminate boilerplate code and solve the problems of scalability with a high level abstraction and a functional programming style
• Slick - Typesafe backed project with Functional Relational Mapping

Check out more about these frameworks at https://stackoverflow.com/questions/1362748/looking-for-a-comparison-of-scala-persistence-frameworks

I've actually written a SQL command shell, in Scala, that talks to any arbitrary database for which a JDBC driver exists. As Brian Agnew notes, it works perfectly. In addition, there are tools like Querulous, SQueryL and OR/Broker that provide Scala-friendly database layers. They sit on top of JDBC, but they provide some additional semantics (via DSLs, in some cases) to make things easier for you.