SQL - 获取当年每个月的最后一天 - SQLITE3答案

【问题标题】：SQL - Get last day of every month of the current year - SQLITE3SQL - 获取当年每个月的最后一天 - SQLITE3
【发布时间】：2018-06-04 12:03:49
【问题描述】：

我匆匆浏览了 SO，发现了很多有用的查询来做到这一点，但不是我想要的，甚至他们说这是答案，但它对 sqlite3 根本不起作用。

所以我们开始吧。我想在当年每个月的最后一天返回所有数据。如下所示：（只是忽略时间，只是想将其添加到我的字段的实际外观）

Name | Date_Added
=================================
Bob  | 2018-01-31 05:23:06.021421
Bob  | 2018-02-28 14:16:03.076021
Bob  | 2018-03-31 13:16:03.076021
Bob  | 2018-04-30 13:16:03.076021
Bob  | 2018-05-31 13:16:03.076021
Bob  | 2018-06-04 13:16:03.076021
Mary | 2018-01-31 13:16:03.076021
Mary | 2018-02-28 13:16:03.076021
Mary | 2018-03-31 13:16:03.076021
Mary | 2018-04-30 13:16:03.076021
Mary | 2018-05-31 13:16:03.076021
Mary | 2018-06-04 13:16:03.076021

我尝试过这样的事情：

SELECT * FROM tableName WHERE date('now','start of month','-1 month','-1 day') ORDER BY "Name"

但它似乎仍然发送不只是最后一天的数据

任何帮助或指导将不胜感激！

【问题讨论】：

标签： sql date sqlite

【解决方案1】：

如果日期是当月的最后一天，那么如果添加一天，月份会有所不同：

SELECT * FROM tableName 
    WHERE 
        strftime("%m", Date_Added) != strftime("%m", Date_Added, "+1 day")
            AND 
        strftime("%Y", Date_Added) = strftime("%Y", "now")
ORDER BY "Name";

【讨论】：

优秀的答案！我的答案是很长的路要走。但是我遇到了一个小问题，我需要获取当月的最后一个数据，所以如果 1 月的最后一个数据是 23 号，那么它必须显示 23 号而不是尝试查询 31 号？我会将您的答案标记为当前问题的正确答案。
是的，这绝对是一个不同的问题。当您发布它时，请务必准确指定您要查找的数据（只是每个月的最后一行？每个月最后一天有数据的所有数据？每个 Name 的每个月的最后一行？ )

【解决方案2】：

SELECT * FROM tableName WHERE
 "Date_added" BETWEEN date('2018-12-30','start of month','-10 month','-1 day') AND date('2018-12-30','start of month','-10 month','0 day') OR 
 "Date_added" BETWEEN date('2018-12-30','start of month','-9 month','-1 day') AND date('2018-12-30','start of month','-9 month','0 day') OR 
 "Date_added" BETWEEN date('2018-12-30','start of month','-8 month','-1 day') AND date('2018-12-30','start of month','-8 month','0 day') OR 
 "Date_added" BETWEEN date('2018-12-30','start of month','-7 month','-1 day') AND date('2018-12-30','start of month','-7 month','0 day') OR 
 "Date_added" BETWEEN date('2018-12-30','start of month','-6 month','-1 day') AND date('2018-12-30','start of month','-6 month','0 day') OR 
 "Date_added" BETWEEN date('2018-12-30','start of month','-5 month','-1 day') AND date('2018-12-30','start of month','-5 month','0 day') OR 
 "Date_added" BETWEEN date('2018-12-30','start of month','-4 month','-1 day') AND date('2018-12-30','start of month','-4 month','0 day') OR 
 "Date_added" BETWEEN date('2018-12-30','start of month','-3 month','-1 day') AND date('2018-12-30','start of month','-3 month','0 day') OR 
 "Date_added" BETWEEN date('2018-12-30','start of month','-2 month','-1 day') AND date('2018-12-30','start of month','-2 month','0 day') OR 
 "Date_added" BETWEEN date('2018-12-30','start of month','-1 month','-1 day') AND date('2018-12-30','start of month','-1 month','0 day') OR 
 "Date_added" BETWEEN date('2018-12-30','start of month','0 month','-1 day') AND date('2018-12-30','start of month','0 month','0 day') 
ORDER BY "Name"

相当乏味，但对我有用！

【讨论】：