FDMEE SQL multi dim mapping

Hi, I'm trying to write a SQL script to map one source dimension to multiple target dimensions. I have a dimension Entity in Planning application and that has 4 attribute dimensions assigned to it. I also have corresponding reporting ASO cube where i have converted all the attribute dims to standard dims. i have SQL script like this

CASE WHEN ENTITY = 'XXXX' THEN 'XXXX' END, UD2X = 'A2', UD3X = 'A3', UD4X='A4'

CASE WHEN ENTITY = 'YYYY' THEN 'YYYY' END, UD2X = 'A2', UD3X = 'A3', UD4X='A4' and so on.

if i just have one line, it works but does not work for more than one case statement. If i map source entity for target entity and then to each standard dims (the ones converted from attribute) it takes forever to load. any thoughts?