DbUnit vs Shoulda comparison of testing frameworks
What are the differences between DbUnit and Shoulda?

DbUnit

http://dbunit.sourceforge.net/

Shoulda

https://github.com/thoughtbot/shoulda
Programming language

Java

Ruby

Category

Unit Testing

General info

Dbunit is a Junit extension for unit testing database driven programs

DbUnit has the ability to export and import your database data to and from XML datasets. Since version 2.0, DbUnit can also work with very large datasets when used in streaming mode and can also help you to verify that your database data match an expected set of values

Meta gem containing Shoulda Context and Shoulda Matchers

Shoulda contains two other gems: Should Context and Shoulda Matchers. Should Context allows better naming and grouping of your tests. Shoulda Matchers provides a set of "matchers", i.e. methods that allow you to write much more concise assertions.
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

Yes

It is a JUnit extension which is one of the most widely known members of the xUnit family

No

Client-side
Allows testing code execution on the client, such as a web browser

No

N/A

Server-side
Allows testing the bahovior of a server-side code

Yes

Yes its used to test database functionality

N/A

Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

N/A

N/A

Group fixtures
Allows defining a fixed, specific states of data for a group of tests (group-fixtures). This ensures specific environment for a given group of tests.

N/A

N/A

Generators
Supports data generators for tests. Data generators generate input data for test. The test is then run for each input data produced in this way.

N/A

N/A

Licence
Licence type governing the use and redistribution of the software

GNU 2.1 License

MIT License

Mocks
Mocks are objects that simulate the behavior of real objects. Using mocks allows testing some part of the code in isolation (with other parts mocked when needed)

No

N/A

Grouping
Allows organizing tests in groups

No

Yes

Other
Other useful information about the testing framework

Shoulda Context is compatible with Minitest and Test::Unit. Shoulda Matchers is compatible with RSpec and Minitest.