Select the column details for table in one column as varchar2(32000)

Question

Oracle Version: ORACLE 10G R 2
Problem : Select the column details for some tables and want to store the same in VARCHAR2(32000) separated by ||
Example:
TABLE_NAME COLUMN_NAME DATA_TYPE
EMP EMPNO NUMBER
EMP ENAME VARCHAR2
EMP JOB VARCHAR2
EMP MGR NUMBER
EMP HIREDATE DATE
EMP SAL NUMBER
EMP COMM NUMBER
EMP DEPTNO NUMBER
EMP RN NUMBER
Want to store
COLUMNS (empno||ename||job||mgr||hiredate||sal||comm||deptno||rn);

Answer 1

SQL> var cur refcursor
SQL> declare
ctx number;
begin
ctx := dbms_xmlgen.newcontext('select * from emp');
dbms_xmlgen.setNullHandling(ctx, dbms_xmlgen.empty_tag);
open :cur for select * from xmltable('for $i in ROW return string-join($i/*, "||")' passing dbms_xmlgen.getxmltype(ctx).extract('ROWSET/ROW'));
end;
PL/SQL procedure successfully completed.
SQL> print cur
COLUMN_VALUE                                                                                       
7369||SMITH||CLERK||7902||17.12.1980 00:00:00||800||||20                                           
7499||ALLEN||SALESMAN||7698||20.02.1981 00:00:00||1600||300||30                                    
7521||WARD||SALESMAN||7698||22.02.1981 00:00:00||1250||500||30                                     
7566||JONES||MANAGER||7839||02.04.1981 00:00:00||2975||||20                                        
7654||MARTIN||SALESMAN||7698||28.09.1981 00:00:00||1250||1400||30                                  
7698||BLAKE||MANAGER||7839||01.05.1981 00:00:00||2850||||30                                        
7782||CLARK||MANAGER||7839||09.06.1981 00:00:00||2450||||10                                        
7788||SCOTT||ANALYST||7566||19.04.1987 00:00:00||3000||||20                                        
7839||KING||PRESIDENT||||17.11.1981 00:00:00||5000||||10                                           
7844||TURNER||SALESMAN||7698||08.09.1981 00:00:00||1500||0||30                                     
7876||ADAMS||CLERK||7788||23.05.1987 00:00:00||1100||||20                                          
7900||JAMES||CLERK||7698||03.12.1981 00:00:00||950||||30                                           
7902||FORD||ANALYST||7566||03.12.1981 00:00:00||3000||||20                                         
7934||MILLER||CLERK||7782||23.01.1982 00:00:00||1300||||10                                         
14 rows selected.