Optimize Complex SQL Joins

How do you optimize a slow-running SQL query containing multiple complex joins?

Assume the provided banking tables contain customers, accounts, transactions, loan applications, and loan payments. Write an optimized PostgreSQL query that returns active customers with active accounts, their in-period transaction totals, latest loan details, and payment totals. Avoid duplicate monetary totals caused by one-to-many joins.

Output

1. One row per active customer with at least one active account.
2. Columns: customer_id, customer_name, active_account_count, transaction_total, latest_loan_id, latest_loan_amount, loan_payment_total.
3. Include customers without loans or in-period transactions, using zero totals where appropriate.
4. Sort by customer_id ascending.