Writing SQL to Retrieve Needed Data | Dataford Interview Questions

How would you write a SQL query to get the data you need for a specific situation?

Using the provided tables, return active customer accounts with unpaid or partially paid invoices due before February 1, 2025. Exclude accounts with no positive outstanding balance.

Output

One row per qualifying account.
Columns: account_id, customer_name, service_type, total_outstanding, and qualifying_invoice_count.
Sort by total_outstanding descending, then account_id ascending.

Schema

customers

Column	Type	Description
customer_idPK	INT	Unique customer identifier
customer_name	VARCHAR(100)	Customer's full name
email	VARCHAR(150)	Customer email address

accounts

Column	Type	Description
account_idPK	INT	Unique service account identifier
customer_id	INT	Customer who owns the account
service_type	VARCHAR(50)	Type of service on the account
status	VARCHAR(20)	Current account status

invoices

Column	Type	Description
invoice_idPK	INT	Unique invoice identifier
account_id	INT	Account billed by the invoice
amount_due	DECIMAL(10,2)	Original invoice amount
amount_paid	DECIMAL(10,2)	Amount paid toward the invoice
due_date	DATE	Invoice payment due date
status	VARCHAR(20)	Invoice payment status

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Problem