CREATE TABLE Customer_Orders (order_id NUMBER, customer_id NUMBER, order_status_code VARCHAR2, shipping_method_code VARCHAR2, order_placed_datetime DATETIME, order_delivered_datetime DATETIME, order_shipping_charges VARCHAR2)
CREATE TABLE Mailshot_Campaigns (mailshot_id NUMBER, product_category VARCHAR2, mailshot_name VARCHAR2, mailshot_start_date DATETIME, mailshot_end_date DATETIME)
CREATE TABLE Customers (customer_id NUMBER, payment_method VARCHAR2, customer_name VARCHAR2, customer_phone VARCHAR2, customer_email VARCHAR2, customer_address VARCHAR2, customer_login VARCHAR2, customer_password VARCHAR2)
CREATE TABLE Customer_Addresses (customer_id NUMBER, premise_id NUMBER, date_address_from DATETIME, address_type_code VARCHAR2, date_address_to DATETIME)
CREATE TABLE Premises (premise_id NUMBER, premises_type VARCHAR2, premise_details VARCHAR2)
CREATE TABLE Products (product_id NUMBER, product_category VARCHAR2, product_name VARCHAR2)
CREATE TABLE Mailshot_Customers (mailshot_id NUMBER, customer_id NUMBER, outcome_code VARCHAR2, mailshot_customer_date DATETIME)
CREATE TABLE Order_Items (item_id NUMBER, order_item_status_code VARCHAR2, order_id NUMBER, product_id NUMBER, item_status_code VARCHAR2, item_delivered_datetime DATETIME, item_order_quantity VARCHAR2)

Show all distinct product categories along with the number of mailshots in each category Visualize by bar chart, and show from high to low by the total number please.
SELECT product_category, COUNT(*) FROM Mailshot_Campaigns GROUP BY product_category ORDER BY COUNT(*) DESC
SELECT "product_category", COUNT(*) FROM "Mailshot_Campaigns" GROUP BY "product_category" ORDER BY COUNT(*) DESC