对于当前周的总计，您需要一个返回日期名称的CTE和另一个返回当前周的星期一的CTE。
您必须交叉连接这些CTE并左连接表以进行聚合：

with 
  days as (
    select 1 nr, 'Monday' day union all
    select 2, 'Tuesday' union all
    select 3, 'Wednesday' union all
    select 4, 'Thursday' union all
    select 5, 'Friday' union all
    select 6, 'Saturday' union all
    select 7, 'Sunday'
  ),
  weekMonday as (
    select date(
        'now', 
        case when strftime('%w', 'now') <> '1' then '-7 day' else '0 day' end, 
        'weekday 1'
      ) monday
  )
select d.day, 
       coalesce(sum(t.quantity), 0) [Sold Items]
from days d cross join weekMonday wm
left join tablename t
on strftime('%w', t.dateTime) + 0 = d.nr % 7
and date(t.dateTime) between wm.monday and date(wm.monday, '6 day')
group by d.nr, d.day
order by d.nr

对于当前年份的总计，您需要一个CTE，它返回月份名称，然后左联接表以进行聚合：

with 
  months as (
    select 1 nr, 'JAN' month union all
    select 2 nr, 'FEB' union all
    select 3 nr, 'MAR' union all
    select 4 nr, 'APR' union all
    select 5 nr, 'MAY' union all
    select 6 nr, 'JUN' union all
    select 7 nr, 'JUL' union all
    select 8 nr, 'AUG' union all
    select 9 nr, 'SEP' union all
    select 10 nr, 'OCT' union all
    select 11 nr, 'NOV' union all
    select 12 nr, 'DEC'
  )
select m.month, 
       coalesce(sum(t.quantity), 0) [Sold Items]
from months m
left join tablename t
on strftime('%m', t.dateTime) + 0 = m.nr
and date(t.dateTime) between date('now','start of year') and date('now','start of year', '1 year', '-1 day')
group by m.nr, m.month
order by m.nr

您可以使用下面的查询来获取每周日期，我假设everydate只有一个条目，因此没有分组，否则您可以添加group by。
首先，我们将得到基于输入日期的周历（我已经采取了当前日期），然后离开加入日历，以获得所需的出售物品信息。

WITH seq(n) AS 
(
  SELECT 0 UNION ALL SELECT n + 1 FROM seq
  WHERE n < DATEDIFF(DAY, (SELECT DATEADD(DAY, 2 - DATEPART(WEEKDAY, GETDATE()), CAST(GETDATE() AS DATE)) [Week_Start_Date]), (Select DATEADD(DAY, 8 - DATEPART(WEEKDAY, GETDATE()), CAST(GETDATE() AS DATE)) [Week_End_Date]))
),
CALENDAR(d) AS 
(
  SELECT DATEADD(DAY, n, (SELECT DATEADD(DAY, 2 - DATEPART(WEEKDAY, GETDATE()), CAST(GETDATE() AS DATE)) [Week_Start_Date])) FROM seq
)
SELECT coalesce(QUANTITY, 0) sold_items ,DATENAME(WEEKDAY, d) week_day FROM CALENDAR a left outer join Table_WEEKDAY b
on (a.d = convert(date, b.dateTime))
ORDER BY d
OPTION (MAXRECURSION 0);

您可以尝试下面的-DEMO

select day,coalesce(sum(quantity),0) as quantity
from 
(select 0 as day union all select 1 union all select 2 union all select 3 union all select 4
union all select 5 union all select 6) as d
left join sales on cast(strftime('%w', dateTime) as int)=day 
group by strftime('%w', dateTime),day
order by day