I would like to understand this as well. I have the same problem with a different database.
I got the same error and found out that this
In the environment extensions, In connections I am not giving the Class Name and not enabled the checkbox(Use Default).
So try with these options, May be helpful for you.
Could you please try the below points
I have got the similar error in the past.I just removed the Semicolon(;) at the end of the SQL Statement.it worked for me.
Retrieving data ...