我正在使用SQL创建步骤漏斗报告。
它返回诸如以下的行：
delivered_email,anonymous_id,opened_email,step1_delivered,step2_opened,step3_landing_page,step4_cta_clicked,steps_completed
email1@example.com,,,true,false,false,false,1
email2@example.com,id2,email2@example.com,true,true,true,true,4
email2@example.com,id3,email2@example.com,true,true,false,false,2
同一电子邮件地址有多个条目，因为这些人参与了多个会话。但是，在这种情况下，我只对完成最多步骤的每个人的会话感兴趣。例如。在上述情况下的实际结果应该有2行而不是3行，其中对于email2@example.com仅在返回steps_completed = 4的情况下：
delivered_email,anonymous_id,opened_email,step1_delivered,step2_opened,step3_landing_page,step4_cta_clicked,steps_completed
email1@example.com,,,true,false,false,false,1
email2@example.com,id2,email2@example.com,true,true,true,true,4
通常，可以通过将结果与每个用户的max(steps_completed)（如described on Stackoverflow）结合在一起来实现。但是，在我的情况下，steps_completed列实际上是作为另一个子查询的一部分计算的。因此，在其上创建联接将需要我复制粘贴整个子查询，这将是无法维护的。
这是查询：
select
*
from
(
-- Counts for each sesssion how many steps were completed
-- This can be used to only select the session with the most steps completed for each unique email address
select
*,
if(step1_delivered, 1, 0) +
if(step2_opened, 1, 0) +
if(step3_landing_page, 1, 0) +
if(step4_cta_clicked, 1, 0)
as steps_completed
from
(
-- Below subquery combines email addresses with associated anonymous_ids
-- Note that a single email may have multiple entries here if they used multiple devices
-- In the rest of the funnel we are interested only in the case grouped by email with the most steps completed
select
t_delivered.email as delivered_email,
t_identifies.id as anonymous_id,
t_opened.email as opened_email,
t_delivered.email is not null as step1_delivered,
coalesce(t_opened.email, t_identifies.id) is not null as step2_opened,
t_landing_page.id is not null as step3_landing_page,
t_cta_clicked.id is not null as step4_cta_clicked
-- Step 1: Retrieve emails to which opener was sent
from
(
select context_traits_email as email
from drip.email_delivered
where email_subject like '%you are invited%'
group by email
) as t_delivered
-- Retrieve the anonymous_id for each email, if set (i.e. if identified)
-- Note that if we have identified a user we will assume they have opened the email
left join
(
select
email,
anonymous_id as id
from javascript.identifies
group by email, anonymous_id
) as t_identifies
on t_identifies.email = t_delivered.email
-- Step 2: retrieve which email addresses opened the opener email
left join
(
select context_traits_email as email
from drip.email_opened
group by email
) as t_opened
on t_opened.email = t_delivered.email
-- Step 3: landing page visited
left join
(
select anonymous_id as id
from javascript.pages
where context_page_title = 'Homepage'
group by anonymous_id
) as t_landing_page
on t_landing_page.id = t_identifies.id
-- Step 4: CTA clicked
left join
(
select anonymous_id as id
from javascript.dtc_file_selection_initiated
group by anonymous_id
) as t_cta_clicked
on t_cta_clicked.id = t_identifies.id
)
)
从本质上讲，我如何将结果按delivered_email分组，而结果（分组之前）却按steps_completed（desc）排序而不重复子查询？
答案 0 :(得分：0)
您应该尝试使用CTE (aka "with clause")和numbering window functions
with
t_delivered as (
select distinct
context_traits_email as email
from
drip.email_delivered
where
email_subject like '%you are invited%'
),
t_identifies as (
-- Retrieve the anonymous_id for each email, if set (i.e. if identified)
-- Note that if we have identified a user we will assume they have opened the email
select distinct
email,
anonymous_id as id
from
`javascript.identifies`
),
t_opened as (
-- Step 2: retrieve which email addresses opened the opener email
select distinct
context_traits_email as email
from
`drip.email_opened`
),
t_landing_page as (
-- Step 3: landing page visited
select distinct
anonymous_id as id
from
`javascript.pages`
where
context_page_title = 'Homepage'
),
t_cta_clicked as (
-- Step 4: CTA clicked
select distinct
anonymous_id as id
from
`javascript.dtc_file_selection_initiated`
),
total_data as (
-- Below subquery combines email addresses with associated anonymous_ids
-- Note that a single email may have multiple entries here if they used multiple devices
-- In the rest of the funnel we are interested only in the case grouped by email with the most steps completed
select
td.email as delivered_email,
ti.id as anonymous_id,
to.email as opened_email,
td.email is not null as step1_delivered,
coalesce(ti.id, to.email) is not null as step2_opened,
tlp.id is not null as step3_landing_page,
tcc.id is not null as step4_cta_clicked
from
t_delivered as td
left join t_identifies as ti on td.email = ti.email
left join t_opened as to on td.email = to.email
left join t_landing_page as tlp on ti.id = tlp.id
left join t_cta_clicked as tcc on ti.id = tcc.id
)
select
*
from
-- Counts for each session how many steps were completed
-- This can be used to only select the session with the most steps completed for each unique email address
( select
*,
row_number() over( partition by
delivered_email
order by -- prioritize columns here
steps_completed desc,
step4_cta_clicked desc,
step3_landing_page desc,
step2_opened desc,
step1_delivered desc,
anonymous_id) as rn
from
( select
*,
if(step1_delivered, 1, 0)
+ if(step2_opened, 1, 0)
+ if(step3_landing_page, 1, 0)
+ if(step4_cta_clicked, 1, 0) as steps_completed
from
total_data
)
)
where
rn = 1