SELECT COUNT(User_ID) FROM Bfriday; -- 信息總數
SELECT COUNT(DISTINCT User_ID) FROM Bfriday; -- 不同用戶數量
SELECT COUNT(DISTINCT Product_ID) FROM Bfriday; -- 不同商品數量
SELECT DISTINCT Age FROM Bfriday ORDER BY Age; -- 不同年齡段
SELECT DISTINCT Occupation FROM Bfriday ORDER BY Occupation; -- 職業類別
SELECT DISTINCT City_Category FROM Bfriday; -- 城市類別
SELECT DISTINCT Stay_In_Current_City_Years FROM Bfriday; -- 居住年限
SELECT DISTINCT Marital_Status FROM Bfriday; -- 婚姻狀況
SELECT DISTINCT Product_Category_1 FROM Bfriday ORDER BY Product_Category_1; -- 商品種類