Show the minimum amount of transactions whose type code is "PUR" and whose share count is bigger than 50.
SELECT min(amount_of_transaction) FROM TRANSACTIONS WHERE transaction_type_code  =  "PUR" AND share_count  >  50
SELECT min(amount_of_transaction) FROM TRANSACTIONS WHERE transaction_type_code  =  "PUR" AND share_count  >  50
[{'min(amount_of_transaction)': 0}]