题解 | 贷款情况

Select
    c.city,
    Sum(la.loan_amount) as total_loan_amount,
    Round(Sum(la.loan_amount) / Count(DISTINCT la.customer_id),2) as average_loan_amount,
    Count(DISTINCT la.customer_id) as total_customers,
    Max(loan_type_name) as most_applied_loan_type
From
    loan_applications la
    Join customers c On la.customer_id = c.customer_id
    Join loan_application_types lap On la.application_id = lap.application_id
    Join loan_types lt On lap.loan_type_id = lt.loan_type_id
Group by
    c.city
Order by
    c.city

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