mysql - 如何在mySQL中选择近月到期

Question

Date    Expiry  Close
20-Mar-18   28-Mar-18   10143.2
20-Mar-18   26-Apr-18   10180.2
20-Mar-18   31-May-18   10201
21-Mar-18   28-Mar-18   10180.2
21-Mar-18   26-Apr-18   10218.3
21-Mar-18   31-May-18   10237.8
22-Mar-18   28-Mar-18   10127.8
22-Mar-18   26-Apr-18   10168.8
22-Mar-18   31-May-18   10193.2
23-Mar-18   28-Mar-18   10003.9
23-Mar-18   26-Apr-18   10047.6
23-Mar-18   31-May-18   10060.2
26-Mar-18   28-Mar-18   10146.2
26-Mar-18   26-Apr-18   10178.3
26-Mar-18   31-May-18   10205
27-Mar-18   28-Mar-18   10179
27-Mar-18   26-Apr-18   10215.8
27-Mar-18   31-May-18   10235.2
28-Mar-18   28-Mar-18   10120.2
28-Mar-18   26-Apr-18   10152
28-Mar-18   31-May-18   10175.3
2-Apr-18    28-Jun-18   10301.4
2-Apr-18    31-May-18   10288.2
2-Apr-18    26-Apr-18   10264
3-Apr-18    26-Apr-18   10285
3-Apr-18    31-May-18   10313.9
3-Apr-18    28-Jun-18   10327.4
4-Apr-18    26-Apr-18   10146.6
4-Apr-18    31-May-18   10175.5
4-Apr-18    28-Jun-18   10194.7
5-Apr-18    26-Apr-18   10352.2
5-Apr-18    31-May-18   10381
5-Apr-18    28-Jun-18   10398
6-Apr-18    28-Jun-18   10399.3
6-Apr-18    31-May-18   10385.1
6-Apr-18    26-Apr-18   10352.8

第一列中的每个日期都有 3 个与其关联的到期日期。我想仅获取最接近日期的到期日(近一个月到期)的日期、关闭、到期日。我该怎么做？谢谢。

例如，我想要的结果是:

Date    Expiry  Close
20-Mar-18   28-Mar-18   10143.2
21-Mar-18   28-Mar-18   10180.2
22-Mar-18   28-Mar-18   10127.8
23-Mar-18   28-Mar-18   10003.9
26-Mar-18   28-Mar-18   10146.2
27-Mar-18   28-Mar-18   10179
28-Mar-18   28-Mar-18   10120.2
2-Apr-18    26-Apr-18   10264
3-Apr-18    26-Apr-18   10285
4-Apr-18    26-Apr-18   10146.6
5-Apr-18    26-Apr-18   10352.2
6-Apr-18    26-Apr-18   10352.8

Answer 1

还没有测试过，我认为在 MariaDB 中这是可行的。请尝试这个:

SELECT
    Date,
    Expiry,
    Close
FROM
    table
GROUP BY
    Date
ORDER BY
    Expiry DESC