SELECT Headquarter, COUNT(DISTINCT T1.Name) FROM Products AS T1 JOIN Manufacturers AS T2 ON T1.Manufacturer = T2.Code
Find the number of different products that are produced by companies at different headquarter cities. Plot them as bar chart.
CREATE TABLE Products (
    Code INTEGER,
    Name VARCHAR(255),
    Price DECIMAL,
    Manufacturer INTEGER
)

CREATE TABLE Manufacturers (
    Code INTEGER,
    Name VARCHAR(255),
    Headquarter VARCHAR(255),
    Founder VARCHAR(255),
    Revenue REAL
)