HI! The PDI online documentation shows a chapter "Inspect your data", which should work using the "fly-out inspection bar" - I am using PDI CE 9.2 and 9.3, but never saw that feature. Is is not available in CE, or does it require specific installation steps?
Data Explorer (DET) is an integration between Spoon and the BA Server's plugins. It is only available in the EE version of the product.