SELECT transaction_type_code, AVG(amount_of_transaction) FROM Transactions GROUP BY transaction_type_code
Create a bar chart showing mean amount of transaction across transaction type code
CREATE TABLE Transactions_Lots (
    transaction_id INTEGER,
    lot_id INTEGER
)

CREATE TABLE Ref_Transaction_Types (
    transaction_type_code VARCHAR(10),
    transaction_type_description VARCHAR(80)
)

CREATE TABLE Lots (
    lot_id INTEGER,
    investor_id INTEGER,
    lot_details VARCHAR(255)
)

CREATE TABLE Sales (
    sales_transaction_id INTEGER,
    sales_details VARCHAR(255)
)

CREATE TABLE Transactions (
    transaction_id INTEGER,
    investor_id INTEGER,
    transaction_type_code VARCHAR(10),
    date_of_transaction DATETIME,
    amount_of_transaction DECIMAL(19,4),
    share_count VARCHAR(40),
    other_details VARCHAR(255)
)

CREATE TABLE Purchases (
    purchase_transaction_id INTEGER,
    purchase_details VARCHAR(255)
)

CREATE TABLE Investors (
    investor_id INTEGER,
    Investor_details VARCHAR(255)
)