CREATE TABLE market (Market_ID INT, District TEXT, Num_of_employees INT, Num_of_shops FLOAT, Ranking INT)
CREATE TABLE phone_market (Market_ID INT, Phone_ID TEXT, Num_of_stock INT)
CREATE TABLE phone (Name TEXT, Phone_ID INT, Memory_in_G INT, Carrier TEXT, Price FLOAT)

What is the number of carriers of phones? Give me a bar chart, could you order in desc by the Carrier?
SELECT Carrier, COUNT(Carrier) FROM phone GROUP BY Carrier ORDER BY Carrier DESC
SELECT "Carrier", COUNT("Carrier") FROM "phone" GROUP BY "Carrier" ORDER BY "Carrier" DESC NULLS LAST