Vertica NULL values issues ! Maybe BUG

 Since last upgrade to 7.2.2 we have faced some issues with NULL values processing. 

This happens when we build temp table based on CTE and NULL values are involved.

I can replicate the strange behaviour as below : 

CTE working fine:

With 
A as ( select Name as Name from db.DimPmaster limit 4 ),
B as ( select NULL                             as Name )
select a.Name from a, b;
     Name
-------------------
 AAAA
 BBBBB
CCCCCC
DDDDDD

With 
A as ( select Name as Name from db.DimPmaster limit 4 ),
B as ( select ''                     as Name )
select a.Name from a, b;
     Name
-------------------
 AAAA
 BBBBB
CCCCCC
DDDDDD

 -- everything works fine when i run my CTE tests. 

Now i want to put this into a temp table.

DROP TABLE IF EXISTS t1; 
CREATE LOCAL TEMP TABLE T1 ON COMMIT PRESERVE ROWS AS
With 
A as ( select brandName as name from db.DimPmaster limit 4),
B as ( select NULL                             as name )
select a.name from a, b;
select * from T1;
 Name
-----------

- i get no data in my temporary table !!! - THIS IS NOT GOOD !!! -- IS THIS A BUG ?  

DROP TABLE IF EXISTS T2;
CREATE LOCAL TEMP TABLE T2 ON COMMIT PRESERVE ROWS AS
With 
A as ( select brandName as name from db.DimPmaster limit 4),
B as ( select ''                     as name )
select a.name from a, b;
SELECT * from T2;
     Name
-------------------
 AAAA
 BBBBB
CCCCCC
DDDDDD

- I GET DATA IN MY TEMP TABLE !??? 

Thanks