你可以簡單地添加其他加入這樣的:
SELECT dashboard_data.headline, dashboard_data.message, dashboard_messages.image_id, images.filename
FROM dashboard_data
INNER JOIN dashboard_messages
ON dashboard_message_id = dashboard_messages.id
INNER JOIN images
ON dashboard_messages.image_id = images.image_id
但是要注意的是,因爲它是一個INNER JOIN
,如果你有沒有圖像的消息時,整個行會被跳過。如果這是一個可能性,你可能想要做一個LEFT OUTER JOIN
將返回所有的板消息且僅當一箇中存在IMAGE_FILENAME(否則你會得到一個null)
SELECT dashboard_data.headline, dashboard_data.message, dashboard_messages.image_id, images.filename
FROM dashboard_data
INNER JOIN dashboard_messages
ON dashboard_message_id = dashboard_messages.id
LEFT OUTER JOIN images
ON dashboard_messages.image_id = images.image_id
http://stackoverflow.com/search?q=mysql+multiple+joins – briantyler