MySQL क्वेरी - URL नामों का उपयोग करके डेटा को इंडेंटिफाई करना जहां डेटा को एक पदानुक्रम में व्यवस्थित किया जाता है

यह संभव होगा यदि आपका DBMS पुनरावर्ती प्रश्नों का समर्थन करता है:

DROP SCHEMA tmp CASCADE;
CREATE SCHEMA tmp ;

CREATE TABLE tmp.webmeuk
    ( id INTEGER NOT NULL PRIMARY KEY
    , slug VARCHAR
    , content_type_id INTEGER NOT NULL
    , parent_id INTEGER REFERENCES tmp.webmeuk(id)
    );
INSERT INTO tmp.webmeuk( id , slug, content_type_id , parent_id )
VALUES(  0 , 'HTTP://pr0n.mysite.xx',    5 , NULL )
    , (  1 , 'portfolio',   5 , 0 )
    , (  2 , 'about-us',    1 , 0 )
    , (  3 , 'find-us',     1 , 0 )
    , (  4 , 'contact-us',  1 , 2 )
    , (  5 , 'find-us',     1 , 4 )
    ;

-- a room with a view
CREATE VIEW tmp.reteview AS (
    WITH RECURSIVE xx AS (
        SELECT w0.id AS id
        , w0.slug AS slug
        , w0.content_type_id AS content_type_id
        , w0.slug AS fullpath
        FROM tmp.webmeuk w0
        WHERE w0.parent_id IS NULL
      UNION 
        SELECT w1.id AS id
        , w1.slug AS slug
        , w1.content_type_id AS content_type_id
        , xx.fullpath || '/'::text || w1.slug AS fullpath
        FROM tmp.webmeuk w1, xx
        WHERE w1.parent_id = xx.id
        )
    SELECT * FROM xx
    );

SELECT * FROM tmp.reteview ;

-- Change one row of data
UPDATE tmp.webmeuk
SET slug = 'what-about-us'
WHERE id = 2;

SELECT * FROM tmp.reteview ;

आउटपुट:

NOTICE:  drop cascades to 2 other objects
DETAIL:  drop cascades to table tmp.webmeuk
drop cascades to view tmp.closure
DROP SCHEMA
CREATE SCHEMA
NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "webmeuk_pkey" for table "webmeuk"
CREATE TABLE
INSERT 0 6
CREATE VIEW
 id |         slug          | content_type_id |                     fullpath                  
----+-----------------------+-----------------+---------------------------------------------------
  0 | HTTP://pr0n.mysite.xx |               5 | HTTP://pr0n.mysite.xx
  1 | portfolio             |               5 | HTTP://pr0n.mysite.xx/portfolio
  2 | about-us              |               1 | HTTP://pr0n.mysite.xx/about-us
  3 | find-us               |               1 | HTTP://pr0n.mysite.xx/find-us
  4 | contact-us            |               1 | HTTP://pr0n.mysite.xx/about-us/contact-us
  5 | find-us               |               1 | HTTP://pr0n.mysite.xx/about-us/contact-us/find-us
(6 rows)

UPDATE 1
 id |         slug          | content_type_id |                        fullpath                    
----+-----------------------+-----------------+--------------------------------------------------------
  0 | HTTP://pr0n.mysite.xx |               5 | HTTP://pr0n.mysite.xx
  1 | portfolio             |               5 | HTTP://pr0n.mysite.xx/portfolio
  3 | find-us               |               1 | HTTP://pr0n.mysite.xx/find-us
  2 | what-about-us         |               1 | HTTP://pr0n.mysite.xx/what-about-us
  4 | contact-us            |               1 | HTTP://pr0n.mysite.xx/what-about-us/contact-us
  5 | find-us               |               1 | HTTP://pr0n.mysite.xx/what-about-us/contact-us/find-us
(6 rows)