Task: Text to Code
Input (English): Step 1: For each row in Policies table, find corresponding rows in Customers table and in Claim_Headers table.
Step 2: find the summation of Amount_Claimed of each value of Customer_Details in the results of step 1.
Step 3: find Customer_Details of the results of step 1 with largest value in the results of step 2
Output (English): SELECT T1.Customer_Details FROM Customers AS T1 JOIN Policies AS T2 ON T1.Customer_ID = T2.Customer_ID JOIN Claim_Headers AS T3 ON T2.Policy_ID = T3.Policy_ID GROUP BY T1.Customer_Details ORDER BY Sum ( T3.Amount_Claimed ) Desc LIMIT 1