sql join 查询日期格式

Question

我正在尝试为我的交易利润制作漂亮的表格视图（在 grafana 中），并按日期对我的交易进行分组。

SELECT
close_date AS "Date",
(SELECT COUNT(*) FROM trades WHERE close_profit > 0 AND c2.close_date = close_date) AS Wins,
(SELECT COUNT(*) FROM trades WHERE close_profit < 0 AND c2.close_date = close_date) AS Losses,
(SELECT AVG(close_profit * 100) FROM trades WHERE c2.close_date = close_date) AS "Avg",
(SELECT SUM(close_profit_abs) FROM trades WHERE c2.close_date = close_date) AS "Profit"
FROM trades c2 WHERE close_date IS NOT NULL GROUP BY close_date

这将创建交易的表格列表，但它不会按日期对交易进行分组，因为原始“close_date”的形式是“2021-09-20 11:11:12.954078 +0000 UTC”。

如何格式化 close_date 以便只有日期 (2021-09-20) 并在连接查询中使用它？ 我试过这个：

SELECT
date(close_date) AS "Date",
.....

这会根据我的需要将 close_date 更改为日期，但随后分组将不起作用。

我尝试将每个 close_date 更改为 date(close_date)，但随后整个语法中断。

SELECT
date(close_date) AS "Date",
(SELECT COUNT(*) FROM trades WHERE close_profit > 0 AND c2.date(close_date) = date(close_date)) AS Wins,
(SELECT COUNT(*) FROM trades WHERE close_profit < 0 AND c2.date(close_date) = date(close_date)) AS Losses,
(SELECT AVG(close_profit * 100) FROM trades WHERE c2.date(close_date) = date(close_date)) AS "Avg",
(SELECT SUM(close_profit_abs) FROM trades WHERE c2.date(close_date) = date(close_date)) AS "Profit"
FROM trades c2 WHERE date(close_date) IS NOT NULL GROUP BY date(close_date)

问题是：

c2.date(close_date)

如何在此处格式化日期时间？

c2.close_date (2021-09-20 11:11:12.954078 +0000 UTC) -> c2.date(close_date) (2021-09-20) ??

感谢您的帮助。我无论如何都不是 sql 专家，所以我的术语可能“有点偏离”。

Answer 1

您可以使用 CAST() 和 CONVERT() 函数

转换您的日期

阅读更多关于这个功能CONVERT() & CAST()

SELECT CONVERT(varchar(10),'2021-09-20 11:11:12.954078 +0000 UTC',105) AS [Date]

Answer 2

请参考此代码

SELECT
            CONVERT(varchar(10),close_date,105) AS "Date",
            (SELECT COUNT(*) FROM trades WHERE close_profit > 0 AND CONVERT(varchar(10),c2.close_date,105) = CONVERT(varchar(10),close_date,105)) AS Wins,
            (SELECT COUNT(*) FROM trades WHERE close_profit < 0 AND CONVERT(varchar(10),c2.close_date,105) = CONVERT(varchar(10),close_date,105)) AS Losses,
            (SELECT AVG(close_profit * 100) FROM trades WHERE CONVERT(varchar(10),c2.close_date,105) = CONVERT(varchar(10),close_date,105)) AS "Avg",
            (SELECT SUM(close_profit_abs) FROM trades WHERE CONVERT(varchar(10),c2.close_date,105) = CONVERT(varchar(10),close_date,105)) AS "Profit"
FROM trades c2 
WHERE CONVERT(varchar(10),close_date,105) IS NOT NULL 
GROUP BY CONVERT(varchar(10),close_date,105)

Answer 3

我能够让它工作。

SELECT
date(close_date) AS "Date",
(SELECT COUNT(*) FROM trades WHERE close_profit > 0 AND date(c2.close_date) = date(close_date)) AS Wins,
(SELECT COUNT(*) FROM trades WHERE close_profit < 0 AND date(c2.close_date) = date(close_date)) AS Losses,
(SELECT AVG(close_profit * 100) FROM trades WHERE date(c2.close_date) = date(close_date)) AS "Avg",
(SELECT SUM(close_profit_abs) FROM trades WHERE date(c2.close_date) = date(close_date)) AS "Profit"
FROM trades c2 WHERE date(close_date) IS NOT NULL GROUP BY date(close_date)