Explain SQL Joins

EasySQL · PostgreSQL00:00

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Your question is Explain SQL Joins. Start with the requirements and the two tables on the right.

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Problem

Explain what SQL is and how joins work.

For the hands-on portion, write a query that returns every customer with their order count and total order value, including customers who have no orders.

Output

One row per customer with customer_id, customer_name, order_count, and total_order_value
Include customers without matching orders with zero totals
Sort by customer_id ascending

Schema

customers

Column	Type	Description
customer_idPK	INT	Unique customer identifier
customer_name	VARCHAR(100)	Customer display name

orders

Column	Type	Description
order_idPK	INT	Unique order identifier
customer_id	INT	Customer associated with the order
order_total	NUMERIC(10,2)	Total value of the order

Tablescustomersorders

Your solutionPostgreSQL

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