Quantas visitas de engenheiro são necessárias no máximo para um único registro de falhas?
CREATE TABLE Fault_Log (fault_log_entry_id VARCHAR); CREATE TABLE Engineer_Visits (fault_log_entry_id VARCHAR)
SELECT COUNT(*), T1.fault_log_entry_id FROM Fault_Log AS T1 JOIN Engineer_Visits AS T2 ON T1.fault_log_entry_id = T2.fault_log_entry_id GROUP BY T1.fault_log_entry_id ORDER BY COUNT(*) DESC LIMIT 1