public override SqlProvider FormatSum(LambdaExpression sumExpression)
{
var selectSql = ResolveExpression.ResolveSum(sumExpression);
var fromTableSql = FormatTableName();
var whereSql = ResolveExpression.ResolveWhereList();
string noneSql = "";
var joinSql = ResolveExpression.ResolveJoinSql(JoinList, ref noneSql);
SqlString = $"{selectSql} {fromTableSql}{joinSql} {whereSql} ";
return(this);
}