sqlite - sqlite数据库的具体区别

Question

对于我需要在 sqlite 中进行的选择，我无法获得正确的查询。我正在尝试获取每个唯一符号的最新日期以及交易方面。它应该是这样的：

date|symbol|side
2021-10-08 10:43:00-04:00|FDX|Sell
2021-10-08 10:44:00-04:00|FDX|Sell
2021-10-08 10:45:00-04:00|FDX|Sell
2021-10-08 10:46:00-04:00|FDX|Sell
2021-10-08 10:47:00-04:00|FDX|Sell
2021-10-08 10:50:00-04:00|FDX|Buy
2021-10-08 10:59:00-04:00|FDX|Sell
2021-10-08 11:00:00-04:00|FDX|Sell
2021-10-08 11:01:00-04:00|FDX|Sell
2021-10-08 11:02:00-04:00|FDX|Sell
2021-10-08 11:03:00-04:00|FDX|Sell
2021-10-08 11:04:00-04:00|FDX|Sell
2021-10-08 11:05:00-04:00|FDX|Sell
2021-10-08 11:06:00-04:00|FDX|Sell
2021-10-08 11:07:00-04:00|FDX|Sell
2021-10-08 11:22:00-04:00|FDX|Sell
2021-10-08 11:23:00-04:00|FDX|Sell
2021-10-08 11:24:00-04:00|FDX|Sell
2021-10-08 11:25:00-04:00|FDX|Sell
2021-10-08 11:26:00-04:00|FDX|Sell
2021-10-08 11:27:00-04:00|FDX|Sell
2021-10-08 11:35:00-04:00|FDX|Sell
2021-10-08 11:36:00-04:00|FDX|Sell
2021-10-08 11:37:00-04:00|FDX|Sell
2021-10-08 11:38:00-04:00|FDX|Sell
2021-10-08 11:39:00-04:00|FDX|Sell
2021-10-08 11:40:00-04:00|FDX|Sell
2021-10-08 11:41:00-04:00|FDX|Sell
2021-10-08 11:42:00-04:00|FDX|Sell
2021-10-08 11:43:00-04:00|FDX|Sell
2021-10-08 11:44:00-04:00|FDX|Sell
2021-10-08 11:45:00-04:00|FDX|Sell
2021-10-08 11:46:00-04:00|FDX|Sell
2021-10-08 11:47:00-04:00|FDX|Sell
2021-10-08 11:48:00-04:00|FDX|Sell
2021-10-08 11:49:00-04:00|FDX|Sell
2021-10-08 11:50:00-04:00|FDX|Sell
2021-10-08 11:51:00-04:00|FDX|Sell
2021-10-08 11:21:00-04:00|LQD|Sell
2021-10-08 11:22:00-04:00|LQD|Sell
2021-10-08 11:23:00-04:00|LQD|Sell
2021-10-08 11:24:00-04:00|LQD|Sell
2021-10-08 11:25:00-04:00|LQD|Sell
2021-10-08 11:26:00-04:00|LQD|Sell
2021-10-08 11:27:00-04:00|LQD|Sell
2021-10-08 11:28:00-04:00|LQD|Sell
2021-10-08 11:29:00-04:00|LQD|Sell
2021-10-08 11:30:00-04:00|LQD|Sell
2021-10-08 11:31:00-04:00|LQD|Sell
2021-10-08 11:53:00-04:00|LQD|Buy
2021-10-08 10:25:00-04:00|QCOM|Sell
2021-10-08 10:26:00-04:00|QCOM|Sell

但我只需要每个符号的最新交易，无论是买入还是卖出

它几乎适用于

select * from (select DISTINCT symbol, side from trades)

symbol|side
FDX|Sell
FDX|Buy
LQD|Sell
LQD|Buy
QCOM|Sell
QCOM|Buy
AGG|Sell
CRSP|Sell
CTXS|Sell
VCIT|Sell
VCIT|Buy
BND|Sell
VCSH|Sell
VCSH|Buy
BSV|Sell
INMD|Sell
PNW|Sell
CHWY|Sell
USIG|Sell
USIG|Buy

但我也需要日期，所以它不太正确。我知道 postgres 有类似的东西，但它在 sqlite 上不可用。是否有可能获得我正在寻找的数据？

预期输出：

2021-10-08 10:43:00-04:00|FDX|Buy
2021-10-08 10:44:00-04:00|FDX|Sell
2021-10-08 10:45:00-04:00|LQD|Buy
2021-10-08 10:46:00-04:00|LQD|Sell
2021-10-08 10:47:00-04:00|QCOM|Sell
2021-10-08 10:50:00-04:00|QCOM|Buy

标签： sqlite