public int seek(int number) {
score score1 = null;

try (Connection c = getConnection(); Statement s = c.createStatement();) {

String sql = "select * from (select *,row_number() over (order by [number]) 'x' from 学生成绩信息) as asd where number=" + number;

ResultSet rs = s.executeQuery(sql);

if (rs.next()) {
score1 = new score();

int Chinesegrade = rs.getInt("x");
score1.number = Chinesegrade;

}

} catch (SQLException e) {

e.printStackTrace();
}
return score1.number;
}

各位大佬，String sql = "select * from (select *,row_number() over (order by [number]) 'x' from 学生成绩信息) as asd where number=" + number; 这句SQL语句怎么理解，特别是那 'x'。