For a concrete SQL Repository, should I encapsulate the SQL logic inside or outside the repository methods?

If I have a concrete repository based on SQL data access, should I pass in SQL to the repository methods or encapsulate them within the methods. I feel if I pass them in, then I am coupling my repository with SQL data access, so I am leaning toward putting the SQL in the methods? Here are my two options:

public GetPeople(string sql)
{
   //Query people with passed in sql
}

public GetPeople()
{
  //Query people with sql logic here, possibly conditional logic
}