Problem Statement

A telecom service system maintains comprehensive information on mobile users, service packages, mobile connections, monthly bills, billing transactions, daily service consumption, and network zones. Schema (the tables that matter for this report) service_packages package_ref INT (PK) package_label VARCHAR(80) package_enabled TINYINT(1) mobile_connections connection_ref INT (PK) package_ref INT (FK → service_packages) connection_state ENUM('ACTIVE', 'BLOCKED', 'CLOSED') daily_service_consumption consumption_ref BIGINT (PK) connection_ref INT (FK → mobile_connections) consumption_date DATE internet_mb INT monthly_service_bills bill_ref INT (PK) connection_ref INT (FK → mobile_connections) cycle_month DATE payable_amount DECIMAL(10,2) bill_state ENUM('OPEN', 'PAID', 'OVERDUE', 'CANCELLED') bill_transactions transaction_ref INT (PK) bill_ref INT (FK → monthly_service_bills) transaction_amount DECIMAL(10,2) transaction_state ENUM('SUCCESS', 'FAILED', 'REFUNDED') Task Pro