CREATE TABLE mailshot_customers (mailshot_id NUMBER, customer_id NUMBER, outcome_code CLOB, mailshot_customer_date TIME)
CREATE TABLE mailshot_campaigns (mailshot_id NUMBER, product_category CLOB, mailshot_name CLOB, mailshot_start_date TIME, mailshot_end_date TIME)
CREATE TABLE customers (customer_id NUMBER, payment_method CLOB, customer_name CLOB, customer_phone CLOB, customer_email CLOB, customer_address CLOB, customer_login CLOB, customer_password CLOB)
CREATE TABLE products (product_id NUMBER, product_category CLOB, product_name CLOB)
CREATE TABLE customer_addresses (customer_id NUMBER, premise_id NUMBER, date_address_from TIME, address_type_code CLOB, date_address_to TIME)
CREATE TABLE customer_orders (order_id NUMBER, customer_id NUMBER, order_status_code CLOB, shipping_method_code CLOB, order_placed_datetime TIME, order_delivered_datetime TIME, order_shipping_charges CLOB)
CREATE TABLE order_items (item_id NUMBER, order_item_status_code CLOB, order_id NUMBER, product_id NUMBER, item_status_code CLOB, item_delivered_datetime TIME, item_order_quantity CLOB)
CREATE TABLE premises (premise_id NUMBER, premises_type CLOB, premise_details CLOB)

Show all distinct product categories along with the number of mailshots in each category.
SELECT product_category, COUNT(*) FROM mailshot_campaigns GROUP BY product_category
SELECT "product_category", COUNT(*) FROM "mailshot_campaigns" GROUP BY "product_category"