HCM 9.0 Query

Hi, hope someone can help. I'm trying to do a simple query that identifies anyone with or without a Workforce Contract. In doing this I assume I would do Left Outer Join on the WKF_CNT_TYPE table  to the Personal Data Table (Im actually using a current personal data staging table). My problem is that it's not given me the full people. Its acting as though I am doing a standard join.   I've been told there is a problem with Left Outer Joins in HCM 9.0.  Please can someone let me know if this is true and how to overcome my problem and output my data.