N level Menu creations

Question

Hi i want to write a query so that it gives me n-level menu tree. the structure of the menu table is as follows :
MENU_ID     INTEGER     number,               
MENU_NAME     VARCHAR2(255)
MENU_TITLE     VARCHAR2(300)
MENU_TITLE_LANG1     VARCHAR2(300)
MENU_TITLE_LANG2     VARCHAR2(300)
MENU_DESCRIPTION VARCHAR2(500)               
MENU_DESCRIPTION_LANG1     VARCHAR2(500)     
MENU_DESCRIPTION_LANG2     VARCHAR2(500)     
MENU_PARENT_ID     NUMBER(10)
MENU_SCREEN_URI     VARCHAR2(1000)
MENU_SCREEN_URI_ADDTNL_PARAM     VARCHAR2(1000)          
SCREEN_TARGET_FRAME     VARCHAR2(50)     
MENU_ICON_URL     VARCHAR2(1000)
STATUS     CLASSIC_SEC_FLAG_TYPE
MAKER_AUTHOR_DETAILS     CLASSIC_SEC_MKR_CHKR_DTLS_TYPE               
the resulting xml has to be in the form :
"<menubar>"+
"<menu text=\"File\" >"+
"<submenu id=\"KJHS\" width=\"100px\">"+
"<item text=\"New\">"+
"<submenu id=\"PZGL\" width=\"110px\">"+
"<item text=\"JPEG\" HREF=\"/Test1/a.faces\" TARGET=\"content\" ></item>"+
"<item text=\"GIF\" HREF=\"/Test1/a.faces\" TARGET=\"content\" ></item>"+
"<item text=\"BMP\" HREF=\"about:blank\">"+
               "<submenu id=\"LPG\" width=\"110px\">"+
                    "<item text=\"JPEG\" HREF=\"/Test1/a.faces\" TARGET=\"content\" />"+
                         "<item text=\"GIF\" HREF=\"http://ittyurl.net/PopularRecent.aspx\" TARGET=\"content\" />"+
               "</submenu>"+
          "</item>"+
"</submenu>"+
"</item>"+
"</submenu>"+
"</menu>"+
"</menubar>"+
if anyone has any idea then do let me know please.......
Regards,
Vikas Kumar

Answer 1

This should help you.
Processing ...
CREATE TABLE TAB_A AS (
     SELECT 'ROOT' AS NAME,1 AS ID,NULL AS PARENT FROM DUAL
     UNION ALL
     SELECT 'SUB-1' AS NAME,2 AS ID,1 AS PARENT FROM DUAL
     UNION ALL
     SELECT 'SUB-1-1' AS NAME,3 AS ID,2 AS PARENT FROM DUAL
     UNION ALL
     SELECT 'IT-1-1' AS NAME,4 AS ID,2 AS PARENT FROM DUAL
     UNION ALL
     SELECT 'IT-1-2' AS NAME,5 AS ID,2 AS PARENT FROM DUAL
     UNION ALL
     SELECT 'IT-1' AS NAME,6 AS ID,1 AS PARENT FROM DUAL
     UNION ALL
     SELECT 'IT-1-3' AS NAME,7 AS ID,2 AS PARENT FROM DUAL
     UNION ALL
     SELECT 'SUB-2' AS NAME,8 AS ID,1 AS PARENT FROM DUAL
     UNION ALL
     SELECT 'IT-2-1' AS NAME,9 AS ID,8 AS PARENT FROM DUAL
     UNION ALL
     SELECT 'IT-1-1-1' AS NAME,10 AS ID,3 AS PARENT FROM DUAL
     UNION ALL
     SELECT 'IT-1-1-2' AS NAME,11 AS ID,3 AS PARENT FROM DUAL
Processing ...
CREATE GLOBAL TEMPORARY TABLE TEMP_TAB AS (
     SELECT LEVEL AS LV,ROWNUM AS RN,A.*
     FROM TAB_A A
     WHERE (1=0)
     START WITH PARENT IS NULL
     CONNECT BY PRIOR ID = PARENT
Processing ...
INSERT INTO TEMP_TAB
     SELECT LEVEL AS LV,ROWNUM AS RN,A.*
     FROM TAB_A A
     START WITH PARENT IS NULL
     CONNECT BY PRIOR ID = PARENT
11 row(s) inserted
Processing ...
SELECT --LV,
     --RN,
     --1+(NVL(LAG(LV) OVER ( ORDER BY RN ASC),0)-LV+1) step,
     --lead(LV) OVER ( ORDER BY RN ASC NULLS LAST) next_lev,
     decode (
          lv-1,
          nvl(
               LAG(LV) OVER ( ORDER BY RN ASC)
               ,0
          '<SUBMENU>',''
     )||'<ITEM>'||NAME||'</ITEM>'||replace(
          RPAD(
               chr(10),
               1+(lv-NVL(
                    lead(LV) OVER ( ORDER BY RN ASC),
                    0
               ))*LENGTH('</SUBMENU>'),
               '</SUBMENU>'
     chr(10),
     ) AS XML_TEXT
FROM TEMP_TAB A
ORDER BY RN ASC
Query finished, retrieving results...
                                    XML_TEXT                                    
<SUBMENU><ITEM>ROOT</ITEM>                                                      
<SUBMENU><ITEM>SUB-1</ITEM>                                                     
<SUBMENU><ITEM>SUB-1-1</ITEM>                                                   
<SUBMENU><ITEM>IT-1-1-1</ITEM>                                                  
<ITEM>IT-1-1-2</ITEM></SUBMENU>                                                 
<ITEM>IT-1-1</ITEM>                                                             
<ITEM>IT-1-2</ITEM>                                                             
<ITEM>IT-1-3</ITEM></SUBMENU>                                                   
<ITEM>IT-1</ITEM>                                                               
<ITEM>SUB-2</ITEM>                                                              
<SUBMENU><ITEM>IT-2-1</ITEM></SUBMENU></SUBMENU></SUBMENU>                      
11 row(s) retrievedBye Alessandro