Given two small tables, one for customers and one for transactions, write a query using aggregate functions to find the total spend per customer.
Return every customer, including customers without transactions. Treat missing transaction amounts as zero.
customer_id, customer_name, and total_spend.customer_id in ascending order.| Column | Type | Description |
|---|---|---|
| customer_idPK | INT | Unique customer identifier |
| customer_name | VARCHAR(100) | Customer's full name |
| Column | Type | Description |
|---|---|---|
| transaction_idPK | INT | Unique transaction identifier |
| customer_id | INT | Customer associated with the transaction |
| amount | DECIMAL(10,2) | Transaction amount |
| transaction_date | DATE | Date the transaction occurred |