PostgreSQL Marketing Report - postgresql

Question

I'm writing out a query that takes ad marketing data from Google Ads, Microsoft, and Taboola and merges it into one table.
The table should have 3 rows, one for each ad company with 4 columns: traffic source (ad company), money spent, sales, and cost per conversion. Right now I'm just dealing with the first 2 till I get those right. The whole table's data should be grouped within that a given month's data.
Right now the results I'm getting are multiple rows from each traffic source, some of them merging months of data into the cost column instead of summing up the costs within a given month.
WITH google_ads AS
( SELECT 'Google' AS traffic_source,
date_trunc('month', "day"::date) AS month,
SUM(cost / 1000000) AS cost
FROM googleads_campaign AS g
GROUP BY month
ORDER BY month DESC),
taboola AS
( SELECT 'Taboola' AS traffic_source,
date_trunc('month', "date"::date) AS month,
SUM(spent) AS cost
FROM taboola_campaign AS t
GROUP BY month
ORDER BY month DESC),
microsoft AS
( SELECT 'Microsoft' AS traffic_source,
date_trunc('month', "TimePeriod"::date) AS month,
SUM("Spend") AS cost
FROM microsoft_campaign AS m
GROUP BY month
ORDER BY month DESC)
SELECT (CASE
WHEN M.traffic_source='Microsoft' THEN M.traffic_source
WHEN T.traffic_source='Taboola' THEN T.traffic_source
WHEN G.traffic_source='Google' THEN G.traffic_source
END) AS traffic_source1,
SUM(CASE
WHEN G.traffic_source='Google' THEN G.cost
WHEN T.traffic_source='Taboola' THEN T.cost
WHEN M.traffic_source='Microsoft' THEN M.cost
END) AS cost,
(CASE
WHEN G.traffic_source='Google' THEN G.month
WHEN T.traffic_source='Taboola' THEN T.month
WHEN M.traffic_source='Microsoft' THEN M.month
END) AS month1
FROM google_ads G
LEFT JOIN taboola T ON G.month = T.month
LEFT JOIN microsoft M ON G.month = M.month
GROUP BY traffic_source1, month1
Here's an example of the results I'm getting. The month column is simply for testing purposes.
| traffic_source1 | cost | month1 |
|:----------------|:-----------|:---------------|
| Google | 210.00 | 01/09/18 00:00 |
| Google | 1,213.00 | 01/10/18 00:00 |
| Google | 2,481.00 | 01/11/18 00:00 |
| Google | 3,503.00 | 01/12/18 00:00 |
| Google | 7,492.00 | 01/01/19 00:00 |
| Microsoft | 22,059.00 | 01/02/19 00:00 |
| Microsoft | 16,958.00 | 01/03/19 00:00 |
| Microsoft | 7,582.00 | 01/04/19 00:00 |
| Microsoft | 76,125.00 | 01/05/19 00:00 |
| Taboola | 37,205.00 | 01/06/19 00:00 |
| Google | 45,910.00 | 01/07/19 00:00 |
| Google | 137,421.00 | 01/08/19 00:00 |
| Google | 29,501.00 | 01/09/19 00:00 |
Instead, it should look like this (Let's say for the month of July this year, for instance):
| traffic_source | cost |
|----------------|-----------|
| Google | 53,901.00 |
| Microsoft | 22,059.00 |
| Taboola | 37,205.00 |
Any help would be greatly appreciated, thanks!

Answer 1

You can try this way:
WITH google_ads AS
( SELECT 'Google' AS traffic_source,
date_trunc('month', "day"::date) AS month,
SUM(cost / 1000000) AS cost
FROM googleads_campaign AS g
GROUP BY month
ORDER BY month DESC),
taboola AS
( SELECT 'Taboola' AS traffic_source,
date_trunc('month', "date"::date) AS month,
SUM(spent) AS cost
FROM taboola_campaign AS t
GROUP BY month
ORDER BY month DESC),
microsoft AS
( SELECT 'Microsoft' AS traffic_source,
date_trunc('month', "TimePeriod"::date) AS month,
SUM("Spend") AS cost
FROM microsoft_campaign AS m
GROUP BY month
ORDER BY month DESC)
SELECT (CASE
WHEN M.traffic_source='Microsoft' THEN M.traffic_source
WHEN T.traffic_source='Taboola' THEN T.traffic_source
WHEN G.traffic_source='Google' THEN G.traffic_source
END) AS traffic_source1,
SUM(CASE
WHEN G.traffic_source='Google' THEN G.cost
WHEN T.traffic_source='Taboola' THEN T.cost
WHEN M.traffic_source='Microsoft' THEN M.cost
END) AS cost,
(CASE
WHEN G.traffic_source='Google' THEN G.month
WHEN T.traffic_source='Taboola' THEN T.month
WHEN M.traffic_source='Microsoft' THEN M.month
END) AS month1
FROM google_ads G
LEFT JOIN taboola T ON G.month = T.month
LEFT JOIN microsoft M ON G.month = M.month
GROUP BY traffic_source1, month1
HAVING EXTRACT(month from month1) = ... desired month (July is 7)

Answer 2

The concept of a different table for each ad source is really a very bad idea. It vastly compounds the complexity of of queries requiring consolidation. It would be much better to have a single table having the source along with the other columns. Consider what happens when marketing decides to use 30-40 or more ad suppliers. If you cannot create a single table then at least standardize column names and types. Also build a view, a materialized view, or a table function (below) which combines all the traffic sources into a single source.
create or replace function consolidated_ad_traffic()
returns table( traffic_source text
, ad_month timestamp with time zone
, ad_cost numeric(11,2)
, ad_sales numeric(11,2)
, conversion_cost numeric(11,6)
)
language sql
AS $$
with ad_sources as
( select 'Google' as traffic_source
, "date" as ad_date
, round(cast (cost AS numeric ) / 1000000.0,2) as cost
, sales
, cost_per_conversion
from googleads_campaign
union all
select 'Taboola'
, "date"
, spent
, sales
, cost_per_conversion
from taboola_campaign
union all
select 'Microsoft'
, "TimePeriod"
, "Spend"
, sales
, cost_per_conversion
from microsoft_campaign
)
select * from ad_sources;
$$;
With a consolidated view of the data you can now write normal selects as though you had a single table. Such as:
select * from consolidated_ad_traffic();
select distinct on( traffic_source, to_char(ad_month, 'mm'))
traffic_source
, to_char(ad_month, 'Mon') "For Month"
, to_char(sum(ad_cost) over(partition by traffic_source, to_char(ad_month, 'Mon')), 'FM99,999,999,990.00') monthly_traffic_cost
, to_char(sum(ad_cost) over(partition by traffic_source), 'FM99,999,999,990.00') total_traffic_cost
from consolidated_ad_traffic();
select traffic_source, sum(ad_cost) ad_cost
from consolidated_ad_traffic()
group by traffic_source
order by traffic_source;
select traffic_source
, to_char(ad_month, 'dd-Mon') "For Month"
, sum(ad_cost) "Monthly Cost"
from consolidated_ad_traffic()
where date_trunc('month',ad_month) = date_trunc('month', date '2019-07-01')
and traffic_source = 'Google'
group by traffic_source, to_char(ad_month, 'dd-Mon') ;
Now this won't do much for updating but will drastically ease selection.