CREATE TABLE Sales (sales_transaction_id INT, sales_details VARCHAR)
CREATE TABLE Lots (lot_id INT, investor_id INT, lot_details VARCHAR)
CREATE TABLE Investors (investor_id INT, Investor_details VARCHAR)
CREATE TABLE Purchases (purchase_transaction_id INT, purchase_details VARCHAR)
CREATE TABLE Ref_Transaction_Types (transaction_type_code VARCHAR, transaction_type_description VARCHAR)
CREATE TABLE Transactions (transaction_id INT, investor_id INT, transaction_type_code VARCHAR, date_of_transaction DATETIME, amount_of_transaction DECIMAL, share_count VARCHAR, other_details VARCHAR)
CREATE TABLE Transactions_Lots (transaction_id INT, lot_id INT)

Show the average transaction amount for different transaction types with a bar chart, and I want to sort by the x-axis in ascending please.
SELECT transaction_type_code, AVG(amount_of_transaction) FROM Transactions GROUP BY transaction_type_code ORDER BY transaction_type_code
SELECT "transaction_type_code", AVG("amount_of_transaction") FROM "Transactions" GROUP BY "transaction_type_code" ORDER BY "transaction_type_code" NULLS FIRST