[User] List vehicle make, model, maintenance service date, and cost for all maintenance logs.

[Assistant] SELECT v.make, v.model, ml.service_date, ml.cost FROM transportation.vehicles AS v JOIN transportation.maintenance_logs AS ml ON v.vehicle_id = ml.vehicle_id;

[User] Filter this list to only include maintenance logs with a cost greater than 500.

[Assistant] SELECT v.make, v.model, ml.service_date, ml.cost FROM transportation.vehicles AS v JOIN transportation.maintenance_logs AS ml ON v.vehicle_id = ml.vehicle_id WHERE ml.cost > 500;

[User] Now, show the average cost of maintenance for each vehicle make, only considering logs where the cost was greater than 500.

[Assistant] SELECT v.make, AVG(ml.cost) AS average_maintenance_cost FROM transportation.vehicles AS v JOIN transportation.maintenance_logs AS ml ON v.vehicle_id = ml.vehicle_id WHERE ml.cost > 500 GROUP BY v.make;

System:
You are an SQL statement expert. Given the table structure described by the CREATE TABLE statement, write an SQL query that provides the solution to the user's question.
##Table Structure
CREATE TABLE transportation.vehicles (
    vehicle_id character varying(64) NOT NULL,  -- unique identifier for the vehicle
    license_plate character varying(32) NOT NULL UNIQUE, -- vehicle license plate
    vin character varying(17) UNIQUE, -- vehicle identification number
    make character varying(64) NOT NULL, -- manufacturer of the vehicle
    model character varying(64) NOT NULL, -- model of the vehicle
    year integer NOT NULL, -- manufacturing year
    type character varying(32) NOT NULL, -- type of vehicle (e.g., Bus, Train, Truck, Car, Van)
    capacity integer, -- passenger or cargo capacity
    fuel_type character varying(32) NOT NULL, -- e.g., Diesel, Gasoline, Electric, Hydrogen
    status character varying(32) NOT NULL, -- e.g., Active, Maintenance, Decommissioned
    depot_id character varying(64), -- identifier of the home depot/base
    acquisition_date date, -- date the vehicle was acquired
    PRIMARY KEY (vehicle_id)
)


[User] Find the top 3 tokens by total supply that have a token symbol starting with 'T', showing their token names, contract addresses, and total supply.

[Assistant] SELECT token_name, contract_address, total_supply FROM web3.tokens WHERE token_symbol LIKE 'T%' ORDER BY total_supply DESC LIMIT 3;

System:
You are an SQL statement expert. Given the table structure described by the CREATE TABLE statement, write an SQL query that provides the solution to the user's question.
##Table Structure
CREATE TABLE web3.tokens ( token_id.text, contract_address.text, token_name.text, token_symbol.text, decimals.integer, total_supply.numeric )