public SqlProvider <T> FormatSum(LambdaExpression lambdaExpression) { var selectSql = ResolveExpression.ResolveSum(typeof(T).GetProperties(), lambdaExpression); var fromTableSql = FormatTableName(); var whereParams = ResolveExpression.ResolveWhere(Context.QuerySet.WhereExpression); var whereSql = whereParams.SqlCmd; Params = whereParams.Param; SqlString = $"{selectSql} {fromTableSql} {whereSql} "; return(this); }