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Ask anything about the SQL Habit platform, Data Analysis, applications of data for running Web or Mobile products, etc.
Hi Anatoli!
I have a question about the funnel analysis query in lesson 129, namely this one:
SELECT
COUNT(h.visitor_id) AS homepage_pvs,
COUNT(b.visitor_id) AS book_page_pvs
FROM web_analytics.pageviews h
LEFT JOIN web_analytics.pageviews b
ON h.visitor_id = b.visitor_id
AND b.url LIKE '%/books/%'
AND (
b.referer_url = 'https://www.bindle.com/'
OR b.referer_url LIKE 'https://www.bindle.com/?%'
)
AND b.created_at BETWEEN h.created_at AND h.created_at + '30 minutes'::interval
WHERE
h.url = 'https://www.bindle.com/'
OR h.url LIKE 'https://www.bindle.com/?%'
My question is: Is the
AND (
b.referer_url = 'https://www.bindle.com/'
OR b.referer_url LIKE 'https://www.bindle.com/?%'
)
bit necessary, given that we filter using WHERE further down? Is there a difference? They seem to give the same results.
In this code where we setup to capture retention, i know we join the table to itself and specify that the left side table has to be a signup action but we never specify what kind of action the right side (joined table) has to be.. doesnt this mean that technically we could be joining a signup action to itself? If thats the case, shouldnt we specify that the joined table’s action can’t be a signup one?
WITH user_activity AS (
SELECT
u.user_id,
u.created_at::date AS signup_date,
e.created_at::date AS activity_date,
COUNT(*) AS events_counts
FROM mobile_analytics.events u
LEFT JOIN mobile_analytics.events e
ON e.user_id = u.user_id
WHERE
u.action = 'signup'
GROUP BY 1, 2, 3
ORDER BY signup_date ASC, user_id ASC
)
SELECT
100.0 * COUNT(DISTINCT(CASE WHEN activity_date = '2018-02-08' THEN user_id END)) / COUNT(DISTINCT(user_id)) AS D7_retention_rate
FROM user_activity
WHERE
signup_date = '2018-02-01'
Hi, im curious to know if this solves the same problem? The answer is correct but i want to make sure my SQL is correct as well in terms of what we’re looking at.
with joined as (
SELECT
a.creative_name,
a.label,
a.activity_kind,
a.adid,
b.event_name
FROM adjust.callbacks a
LEFT JOIN adjust.callbacks b
ON a.adid = b.adid
and b.event_name = 'signup'
WHERE a.tracker = 'gxel3d1'
AND a.activity_kind = 'click'
), numbers as (
SELECT
creative_name,
count(distinct(case when event_name = 'signup' then adid end)) as signups,
count(distinct(adid)) as total
FROM joined
GROUP BY 1
)
SELECT
*,
100.0*signups/total
from numbers
order by 2 desc
In the following code from Lesson 109.. how come we dont need to group by utm_campaign at the end when we are calculating CPA? is it because we joined the users to the row by utm_campaign?
WITH spend_per_campaign AS (
SELECT
utm_campaign,
SUM(amount) AS total_spend
FROM marketing_spends
GROUP BY 1
), users_per_campaign AS (
SELECT
utm_campaign,
COUNT(*) AS users_count
FROM users
WHERE
utm_campaign IS NOT NULL
GROUP BY 1
)
SELECT
s.utm_campaign,
users_count,
total_spend / users_count AS CPA
FROM spend_per_campaign s
INNER JOIN users_per_campaign u
ON s.utm_campaign= u.utm_campaign
Does this look correct for the homework at the bottom of lesson 108 where it asks to add country to the CTE?
I chose inner join instead of left join but i dont think it would matter if i did left join?
WITH customers AS (
SELECT
a.user_id,
b.country,
MIN(a.created_at) AS first_purchased_at
FROM purchases a
inner join users b
on a.user_id = b.id
WHERE
refunded = FALSE
GROUP BY 1,2
ORDER BY 3 DESC
)
SELECT *
FROM customers
How to distinguish between direct visits, referral visits and clicks from organic search when tracking with a custom pixel? In the course, the main info on campaigns comes from UTMs from the URL, but you would also wanna analyze organic traffic, that does not usually have tracking parameters in a link.