List function in repository

[samaremad]

hi everyone can you please help me ?

i want to use list function so that each time this function called then it will counting records of data and store it in a feild
as example :

var count=db.voterecords.where(x=>x.unionid.equals(request.unionid).count();
s.num=count;

what suppose i write in (request.unionid)?