Subqueries in Logical SQL

Summary

I've probably failed at some simple syntax..

Content

Attempting to build some fairly complex queries using Logical SQL Analysis in OTBI.

This query:
SELECT
"Worker"."Person Number",
"Worker"."Employee List Name",
"Worker"."Person Type"
FROM "Workforce Management - Worker Assignment Real Time"

Does exactly what you'd expect

 

This query:

SELECT
A.PerNum,
A.EmpName,
A.PerType

FROM
(
SELECT
"Worker"."Person Number" PerNum,
"Worker"."Employee List Name" EmpName,
"Worker"."Person Type" PerType
FROM "Workforce Management - Worker Assignment Real Time"
) A

Throws the following error:

 

View Display Error 

Error generating view. Error getting cursor in GenerateHead

  Error Details

Error Codes: