CREATE TABLE cable_maintenance_logs (
id INTEGER PRIMARY KEY AUTOINCREMENT,
cable_route_id INTEGER,
network_segment_id INTEGER,
maintenance_type VARCHAR(50) NOT NULL CHECK (maintenance_type IN ('repair', 'replacement', 'inspection', 'upgrade')),
description TEXT NOT NULL,
performed_by INTEGER,
maintenance_date DATE NOT NULL,
duration_hours DECIMAL(4,2),
cost DECIMAL(12,2),
notes TEXT,
created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
FOREIGN KEY (cable_route_id) REFERENCES cable_routes(id) ON DELETE CASCADE,
FOREIGN KEY (network_segment_id) REFERENCES network_segments(id) ON DELETE CASCADE
)