- Connect to a MySQL database
- Create a table, e.g. 'CREATE TABLE test (id int primary key)'
- In the Show Data editor, run 'SELECT * from test'
- You get the error 'table TEST not found...'

If I try 'select * from test' in the standard SQL editor it works fine.

Two things: 
- the dialog is not that helpful, it would be nice if it showed the SQL that failed
- it is interesting to note that 'TEST' is capitalized in the error message