mysql查詢從給定的表結構創建SEO友好的URL

Question

我正在嘗試使用下表創建SEO友好的URL：

分類表

頁數表

我正在嘗試編寫一個mysql查詢，它將使用產生以下輸出的類別表為pages表中的所有頁面生成URL。

預期的輸出：

這是我嘗試生成最多4個段的URL的MySql查詢：

SELECT pg.id AS page_id, p3.id, p1.category AS segment1, p2.category AS segment2, p3.category AS segment3, 
pg.page_name AS PAGE , concat( '/', p1.category, '/', p2.category, '/', p3.category, '/', pg.page_name, '/' ) AS url
FROM category AS p1, category AS p2, category AS p3, pages AS pg
WHERE pg.category_id = p3.id
AND p3.parent_id = p2.id
AND p2.parent_id = p1.id

鏈接到SQL Fiddle

Answer 1

這是我自己的問題的答案：

我嘗試使用“ MySql Modified preorder tree to create url ”方法，該方法在查詢優化和通過stackoverflow進行的其他研究方面更有用。

Answer 2

不是最好的解決方案，但是它有效 ;）

SELECT pagetable.id AS page_id
, c1.id
, pagetable.page_name AS PAGE 
, concat( 
    IF(c3.category IS NULL,'','/')
  , IF(c3.category IS NULL,'',c3.category)
  , IF(c2.category IS NULL,'','/')
  , IF(c2.category IS NULL,'',c2.category)
  , IF(c1.category IS NULL,'','/')
  , IF(c1.category IS NULL,'',c1.category)
  , '/'
  , pagetable.page_name
  , '/' ) AS url
FROM pages AS pagetable 
LEFT JOIN category AS c1
ON pagetable.category_id = c1.id
LEFT JOIN category AS c2
ON c1.parent_id = c2.id
LEFT JOIN category AS c3
ON c2.parent_id = c3.id