Question

我有一个包含StormID列和ModelBaseTime列的表（以及其他一些列）..

我试图获取StormID =＆＃39; AL012015＆＃39;的所有记录和所有字段。并且只有那些具有针对该特定StormID的最新ModelBaseTime的记录。

这是我通过研究SO所尝试的。

SELECT * FROM adeck_raw WHERE StormID = 'AL012015' 
AND ModelBaseTime IN(SELECT MAX(ModelBaseTime))
ORDER BY StormID;

^^这会使用多个ModelBaseTime而不是最新的ModelBaseTime返回太多结果。

SELECT * FROM adeck_raw 
WHERE StormID = 'AL012015' AND ModelBaseTime IN
    (SELECT MAX(ModelBaseTime)
     FROM adeck_raw
     GROUP BY StormID
    )
GROUP BY StormID
ORDER BY ModelBaseTime;

^^这会返回1条记录（我知道有多条记录）

SELECT * adeck_raw AS t
CROSS JOIN (
SELECT StormID, MAX(ModelBaseTime) AS latest_date FROM adeck_raw WHERE StormdID = 'AL012015' GROUP BY StormID
) AS sq
USING (StormID, ModelBaseTime);

^^这不执行... sql语法错误

SELECT*, MAX(ModelBaseTime)
FROM adeck_raw WHERE StormID = 'AL012015'
GROUP BY StormID;

^^这只返回1条记录

感谢您的任何建议和示例。布赖恩

Answer 1

试试这个：

SELECT t1.* 
FROM adeck_raw AS t1
INNER JOIN (
   SELECT MAX(ModelBaseTime) AS latest_date
   FROM adeck_raw
   WHERE StormID = 'AL012015'
) AS t2 ON t1.ModelBaseTime = t2.latest_date
WHERE StormID = 'AL012015';

MySQL使用WHERE子句选择具有最新可用日期的行

1 个答案: