Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE TRANSACTIONS (amount_of_transaction INTEGER, transaction_type_code VARCHAR)

### Question ###
Show the average amount of transactions with type code "SALE".

### Accurate SQL ###

SELECT AVG(amount_of_transaction) FROM TRANSACTIONS WHERE transaction_type_code = "SALE"