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The Full-Service Users

hardSQLGroupByHAVING

Northline Bank counts a customer as fully engaged once they have used every kind of movement the bank offers — they have deposited, withdrawn and transferred. Those customers are the ones the product team studies, because they have met every part of the product. Depositing five times is still one kind of movement.

transactions — one row per movement of money. customer_id points at a row in customers; type is one of deposit, withdrawal or transfer; txn_date is the day it settled. The ledger is signed: money arriving in an account is stored as a positive amount, and money leaving it as a negative one, so a 600-dollar withdrawal is recorded as -600.

id customer_id amount type txn_date
1 1 500 deposit 2023-07-01
2 1 -120 withdrawal 2023-07-03
3 2 1000 deposit 2023-07-02
4 2 -300 withdrawal 2023-07-05
5 3 250 deposit 2023-07-04
6 3 -600 withdrawal 2023-07-06
7 4 800 deposit 2023-07-07
8 4 -450 withdrawal 2023-07-08
9 5 2000 deposit 2023-07-09
10 5 -1500 withdrawal 2023-07-10
11 1 -200 transfer 2023-07-11
12 3 400 deposit 2023-07-12

The table already exists in the database — there is nothing to create or load.

Task: Write a query that returns a single column, customer_id, listing every customer who has used all three kinds of movement, sorted by customer_id from smallest to largest. Customers who have used only one or two kinds must not appear.

Example output — shape only, on invented customers. If two people had used every kind of movement, you would get:

customer_id
13
17

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