INNER JOINのテーブルの1つからユニークな行を取得

Question

zc_ordersテーブルにある一意の行を取得するための回避策はありますか？私はzc_zc_orders_status_history（重複する行を持つ）からのコメントフィールドのみが必要です。これは私のクエリです：

SELECT 
zc_orders.orders_id, 
zc_orders_status_history.comments, 
zc_orders_status_history.orders_status_id, 
zc_customers.customers_email_address, 
zc_customers.customers_telephone, 
zc_customers.customers_firstname, 
zc_customers.customers_lastname, 
zc_orders_status_history.date_added, 
zc_orders.date_purchased 
FROM 
zc_customers 
INNER JOIN zc_orders ON zc_orders.customers_id = zc_customers.customers_id 
INNER JOIN zc_orders_status_history ON 
zc_orders_status_history.orders_id = zc_orders.orders_id 
where zc_orders_status_history.orders_status_id = 8 
ORDER BY zc_orders_status_history.date_added DESC 

Answer 1

SELECT DISTINCT 
zc_orders_status_history.comments, 
FROM 
zc_customers 
INNER JOIN zc_orders ON zc_orders.customers_id = zc_customers.customers_id 
INNER JOIN zc_orders_status_history ON 
zc_orders_status_history.orders_id = zc_orders.orders_id 
where zc_orders_status_history.orders_status_id = 8 
ORDER BY zc_orders_status_history.date_added DESC