public IEnumerable <Candidate> SearchCandidates(SearchCandidate filter)
{
//var p1 = new SqlParameter("@Id", id);
//var author = db.Authors.FromSqlRaw($"SELECT * From Authors Where AuthorId = @Id", p1).FirstOrDefault()
var whereCondition = BuildQuery.ConcatStringFilters(filter);
var candidates = context.Candidates.FromSqlRaw($"select * from Candidates {whereCondition}");
return(candidates.ToList());
}