我有来自不同销售点的大量销售。我想创建一个 MySql 查询，该查询将按日期和商店对销售交易进行分组，同时有一列显示上一年在一周中最近一天的销售额。
这是我的数据集：
|id |folderCounter_id|incasso |scontrini|timestamp |
|-------|----------------|--------|---------|-------------------|
|189.712|131 |783,61 |4 |2024-01-08 06:00:00|
|189.713|131 |531,41 |36 |2024-01-08 08:00:00|
|189.714|131 |2.650,45|74 |2024-01-08 09:00:00|
|189.715|131 |4.140,04|141 |2024-01-08 10:00:00|
|189.716|131 |5.236,63|142 |2024-01-08 11:00:00|
|189.717|131 |7.043,62|202 |2024-01-08 12:00:00|
|189.718|131 |3.796,72|118 |2024-01-08 13:00:00|
|189.719|131 |4.375,61|118 |2024-01-08 14:00:00|
|189.720|131 |4.125,11|137 |2024-01-08 15:00:00|
|189.721|131 |4.346,73|134 |2024-01-08 16:00:00|
|189.722|131 |4.848,3 |144 |2024-01-08 17:00:00|
|189.723|131 |6.408,3 |209 |2024-01-08 18:00:00|
|189.724|131 |6.270,29|176 |2024-01-08 19:00:00|
|189.725|131 |3.482,77|113 |2024-01-08 20:00:00|
|189.726|131 |115,24 |2 |2024-01-08 21:00:00|
|189.727|53 |0 |0 |2024-01-08 07:00:00|
|189.728|53 |671,49 |50 |2024-01-08 08:00:00|
|189.729|53 |1.519,28|73 |2024-01-08 09:00:00|
|189.730|53 |2.918,88|122 |2024-01-08 10:00:00|
|189.731|53 |5.628,6 |184 |2024-01-08 11:00:00|
|189.732|53 |4.880,91|165 |2024-01-08 12:00:00|
|189.733|53 |3.288,26|116 |2024-01-08 13:00:00|
|189.734|53 |1.908,28|85 |2024-01-08 14:00:00|
|189.735|53 |3.786,79|113 |2024-01-08 15:00:00|
.
.
.
|189.736|131 |3.672,45|115 |2023-01-09 07:00:00|
|189.737|131 |5.241,46|164 |2023-01-09 09:00:00|
|189.738|131 |5.776,72|162 |2023-01-09 10:00:00|
|189.739|131 |5.830,12|190 |2023-01-09 12:00:00|
|189.740|131 |2.726,45|85 |2023-01-09 13:00:00|
|189.741|131 |0 |0 |2023-01-09 14:00:00|
|189.742|131 |0 |0 |2023-01-09 15:00:00|
|189.743|131 |1.152,64|42 |2023-01-09 16:00:00|
我创建了这个查询：
select t1.date as 'timestamp', t1.folderCounter_id as 'folderCounter_id', t1.incasso as
'incasso', t2.incasso as 'last_yr_incasso', t1.scontrini as 'scontrini', t2.scontrini
as 'last_yr_scontrini'
from(
SELECT cr.`timestamp` as date, cr.folderCounter_id, cr.incasso as incasso, cr.scontrini
as scontrini
from CashRegister cr
group by cr.`timestamp`, cr.folderCounter_id
) t1
left join(
SELECT cr.`timestamp` as date, cr.incasso as incasso, cr.scontrini as scontrini
from CashRegister cr
group by cr.`timestamp`, cr.folderCounter_id
) t2
on DATE_SUB(t1.date, INTERVAL 52 WEEK) = t2.date
order by t1.date asc
但是，它不会返回 t1 上不存在的第一个表 t2 的值。
|timestamp |folderCounter_id|incasso |last_yr_incasso|scontrini|last_yr_contrini|
|-------------------|----------------|--------|---------------|---------|----------------|
|2024-01-08 07:00:00|131 |NULL |3.672,45 |NULL |115 |
如何修改查询以便它也返回不存在的值？ 所有时间戳，包括上一年的时间戳，都必须包含在第一列中。
我尝试进行完整的外连接，但无法创建带有时间戳的单个列（在这种情况下，我必须创建 2 个列，否则第一个列具有 NULL 值）
您必须收集所有日期，然后将两个表左连接到其中。
示意图：
SELECT *
-- collect all existing datetimes, with according correction
FROM (SELECT timestamp FROM table WHERE YEAR(timestamp) = 2024
UNION DISTINCT
SELECT timestamp + INTERVAL 52 WEEK FROM table WHERE YEAR(timestamp) = 2023) AS dates
-- join existing data for 2024
LEFT JOIN table t1 ON dates.timestamp = t1.timestamp AND YEAR(timestamp) = 2024
-- join existing data for 2023
LEFT JOIN table t2 ON dates.timestamp - INTERVAL 52 WEEK = t2.timestamp AND YEAR(timestamp) = 2023