Duplicate Invoice SQL Logic | Dataford Interview Questions

Write a SQL query to identify vendors who have submitted multiple invoices with the exact same dollar amount on the same day.

Use the vendors and invoices tables. Include only duplicate invoice combinations where the vendor, invoice date, and dollar amount are all present.

Output

One row per vendor, date, and invoice amount combination with multiple invoices.
Columns: vendor_id, vendor_name, invoice_date, invoice_amount, invoice_count, and invoice_ids.
Sort by vendor_id, invoice_date, and invoice_amount in ascending order.

Schema

vendors

Column	Type	Description
vendor_idPK	INT	Unique vendor identifier
vendor_name	VARCHAR(150)	Vendor legal or trading name

invoices

Column	Type	Description
invoice_idPK	INT	Unique invoice identifier
vendor_id	INT	Vendor that submitted the invoice
invoice_date	DATE	Date the invoice was submitted
invoice_amount	NUMERIC(12,2)	Invoice amount in dollars

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