How to get list of all employees in a Descriptive Flex field(DFF)

Summary:

Hi,

We need to get list of employees in LOV of HRG descriptive flexfield. We have created a new category of performance goal (Cross Functional) and also created a DFF(Cross Functional Manager). Now we want the LOV to show existing list of employees from system so that employee can select his cross functional manager while adding his new performance goal.

in DFF's LOV we cannot add more than 500 entries in standard, but can we get the list of existing employees through groovy expression or SQL? or is there any other workaround to get existing employees data in a DFF?