使用 between in where 子句在 Snowflake 中加入 table

Question

我有周table -

Week,   Friday_dates,   Start_date, End_date
1,      2021-07-16,     2021-07-12, 2021-07-18
2,      2021-07-23,     2021-07-19, 2021-07-25

等等..

我还有另一个 table，其中包含按日期列出的详细信息列表

Date,        To_do_list
20220-01-02, Text 
20220-01-03, Call
20220-01-03, Text
20220-01-04, Call
20220-01-05, Call

我想要 to_do_list 的计数，上面写着 Call and want join this table with date table for specific dates falling under start_date and end_date.

有人能帮帮我吗？

Answer 1

鉴于您的数据（我使用的是 CTE，所以我不必创建表格）

WITH Weeks(Week, Friday_dates, Start_date, End_date) as (
    SELECT * FROM VALUES
    (1, '2021-07-16'::date, '2021-07-12'::date, '2021-07-18'::date),
    (2, '2021-07-23'::date, '2021-07-19'::date, '2021-07-25'::date)
), Activity(Date, To_do_list) as (
    SELECT * FROM VALUES
    ('20220-01-02'::date, 'Text'),
    ('20220-01-03'::date, 'Call'),
    ('20220-01-03'::date, 'Text'),
    ('20220-01-04'::date, 'Call'),
    ('20220-01-05'::date, 'Call')
)

要将 activity 加入 weeks 并将计数限制为每周计数的通话次数，您将：

SELECT w.Friday_dates
    ,count(*) as call_count
FROM Activity AS a
JOIN Weeks AS w
    on a.DATE between w.Start_date and w.End_date
WHERE a.To_do_list = 'Call'
GROUP BY 1
ORDER BY 1;

没有结果，因为您的 none 周与 activity 时间范围重叠。

因此，如果我们将数据更改为重叠：

WITH Weeks(Week, Friday_dates, Start_date, End_date) as (
    SELECT * FROM VALUES
    (1, '2021-07-16'::date, '2021-07-12'::date, '2021-07-18'::date),
    (2, '2021-07-23'::date, '2021-07-19'::date, '2021-07-25'::date)
), Activity(Date, To_do_list) as (
    SELECT * FROM VALUES
    ('2021-07-18'::date, 'Text'),
    ('2021-07-18'::date, 'Call'),
    ('2021-07-18'::date, 'Text'),
    ('2021-07-19'::date, 'Call'),
    ('2021-07-20'::date, 'Call')
)

我们现在得到：

FRIDAY_DATES	CALL_COUNT
2021-07-16	1
2021-07-23	2

但是如果我们从评论中提取您 SQL 并使其有效：

select * from Weeks a 
left join (
    select Date, 
        count(*) from Activity 
    where To_do_list like '%Call%' 
    group by DATE
) b 
    on b.DATE between a.Start_date and a.End_date 
ORDER BY 1;

我们得到..

WEEK	FRIDAY_DATES	START_DATE	END_DATE	DATE	COUNT(*)
1	2021-07-16	2021-07-12	2021-07-18	2021-07-18	1
2	2021-07-23	2021-07-19	2021-07-25	2021-07-19	1
2	2021-07-23	2021-07-19	2021-07-25	2021-07-20	1

使用 between in where 子句在 Snowflake 中加入 table

Join table in Snowflake using between in where clause

mysql

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