how to show values from 2 columns in LOV

I'm working on one requirement where user can set the start and end date with time while creating an entry. later if he wants to edit, user cal see the time which he has been set earlier and change it accordingly. I've to show the number of existing records to the user with start and end date and time. My LOV query is below, but it gives me the below error.

My LOV Query:

select start_date || ' - ' || EXTRACT(HOUR FROM end_date) || ':' ||

EXTRACT(MINUTE FROM end_date) as display,  cal_entry_id as value from crs_resource_cal_entries