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Account-Level MRR

mediumSQLJoinsGroupByNULLs

Loopwire's customer-success team is drawing up its attention list, and the ranking has to be by customer rather than by contract — a company paying for two things at once is worth the sum of both, and the contract table on its own will never tell you that. MRR is monthly recurring revenue: what a live contract bills each month. Companies with nothing running are somebody else's problem this week.

subscriptions — one row per contract. account_id points at a row in accounts. plan is the tier the customer bought. mrr is what that contract bills every month, in dollars. start_date is the day it began. A contract that has stopped carries the day it stopped in end_date; one that is still running has nothing there, shown as below and stored as NULL.

id account_id plan mrr start_date end_date
1 1 starter 49 2022-11-03 2023-02-03
2 1 growth 149 2023-02-03
3 2 growth 149 2022-12-15 2023-06-15
4 3 starter 49 2023-01-31
5 4 growth 149 2023-02-06
6 5 enterprise 499 2023-02-22
7 6 starter 49 2023-03-01 2023-04-01
8 7 growth 149 2023-03-22
9 8 enterprise 499 2023-04-28
10 2 starter 49 2023-06-15

accounts — one row per customer company. industry is the sector that company works in; signup_date is the day it created its Loopwire account.

id company_name industry signup_date
1 Northwind Traders retail 2022-11-03
2 Vertex Analytics software 2022-12-15
3 Bluepeak Logistics logistics 2023-01-20
4 Fernwood Studio media 2023-02-05
5 Cobalt Health healthcare 2023-02-18
6 Ridgeline Capital finance 2023-03-01
7 Sable & Co retail 2023-03-22
8 Hearth Robotics manufacturing 2023-04-10

Both tables already exist in the database — there is nothing to create or load.

Task: Write a query that returns one row per company that has at least one running contract, with columns company_name and account_mrr, account_mrr being that company's combined monthly billing across its running contracts. Largest first; equal amounts are listed alphabetically by company name.

Example output

Shape only — these companies and figures are invented:

company_name account_mrr
Ironvale Systems 900
Tidewater Farms 640
Larkspur Freight 300
Orbit Grocers 300
Quill & Bright 75

(...2 more rows not shown)

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