2多對多關係 - 通過連接提取數據

Question

請檢查下面鏈接中的模式。

http://s11.postimg.org/dydr5ru3n/stack.png

我想選擇所有特性，同時代理和每個屬性的所有者。問題是代理人和所有者的細節來自同一張表，並且存在衝突。

我應該遵循什麼解決方案？

注意：不幸的是我無法更改數據庫模式。

Answer 1

SELECT oPers.first_name AS ownerFirstName 
    , aPers.first_name AS agentFirstName 
    .... 
FROM properties AS p 
LEFT JOIN owners AS po ON p.property_id = po.property_id 
LEFT JOIN people AS oPers ON po.person_id = oPers.person_id 
LEFT JOIN agents AS pa ON p.property_id = pa.property_id 
LEFT JOIN people AS aPers ON pa.person_id = aPers.person_id 
;