This Oml will help you to fetch data in the grid

and also refer to this link 

https://success.outsystems.com/documentation/11/building_apps/user_interface/patterns/using_mobile_and_reactive_patterns/interaction/outsystems_data_grid/how_to_use_the_outsystems_data_grid/?_gl=1*6j9yxb*_gcl_au*MTQ4MjA2NTcyNS4xNzYwNDIzNTY0*_ga*MTk2OTk2MjU4OS4xNzYwNDIzNTY3*_ga_ZD4DTMHWR2*czE3NjA0MjM1NjYkbzEkZzEkdDE3NjA0NDYwMjEkajU0JGwwJGgw*_ga_HGKNZZMWJS*czE3NjA0NDU3MDkkbzUkZzEkdDE3NjA0NDYwMjEkajU0JGwxJGgyMDI3OTI4NTgw*_ga_G11QMS1MBT*czE3NjA0NDU3MDgkbzUkZzEkdDE3NjA0NDYwMjAkajU1JGwwJGgw