java - 从结果集中检索结果 mysql java

Question

在Java中。有谁知道如何从此查询中检索数据？我可以为简单的查询执行此操作，但我发现这种情况非常令人困惑:

SELECT (SELECT sum(r2.a) FROM R r2 WHERE year(r2.p) = 
'2015' and month(r2.p) < month(r1.p) ) AS Previous,
            (SELECT sum(r3.a) FROM R r3 WHERE year(r3.p) 
 = '2015' and month(r3.p) > month(r1.p) ) AS Next,
            (SELECT sum(r4.a) FROM R r4 WHERE year(r4.p) 
 = '2015' and month(r4.p) = month(r1.p) ) AS Curr
 FROM R r1
  WHERE YEAR(r1.pickupdate) = '2015';

Answer 1

使用声明的别名:AS Curr

ResultSet rs = preparedStatement.executeQuery();

while (rs.next()) {
        Integer curr = rs.getInt("Curr");
        // Do something here
}