Pivote a string

Question

Hi Forum ,
I have a table test12 like below (name and value are 2 columns of the table)
name value
app1     aw
app1     br
app1     sdf
app1     dx
app1     esd
app2     aw
app2     dx
app2     esd
scripts :
create table test12 ( name varchar2(100),value varchar2(100));
insert into test12 values('app1','aw');
insert into test12 values('app1','br');
insert into test12 values('app1','sdf');
insert into test12 values('app1','dx');
insert into test12 values('app1','esd');
insert into test12 values('app1','aw');
insert into test12 values('app2','dx');
insert into test12 values('app2','esd');
commit;
select * from test12;
and I have to write a query to see above data as below
col1 col2 col3 col4 col5 col6
app1 aw br sdf dx esd
app2 aw dx esd
--here the values will grow dynamically and our query should able to add new column like col7,col8 ..
Please let me know for more info .
select * from v$version;
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE 11.2.0.2.0 Production
TNS for Linux: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production
Thanks ,
Mahesh

Answer 1

A basic attempt at implementing Frank's dynamic pivot method as an object class in Oracle:
SQL> create or replace type TStringArray is table of varchar2(4000);
  2  /
Type created.
SQL>
SQL> create or replace type TDynamicPivot is object(
  2          table_name              varchar2(30),
  3          standard_columns        varchar2(4000),
  4          pivot_column            varchar2(30),
  5          order_by                varchar2(4000),
  6          column_name             TStringArray,
  7          column_values           TStringArray,
  8 
  9          member function GetSQL return varchar2,
10          member function GetRefCursor return sys_refcursor
11  );
12  /
Type created.
SQL>
SQL> create or replace type body TDynamicPivot as
  2 
  3          member function GetSQL return varchar2 is
  4                  sqlSelect       varchar2(32767);
  5          begin
  6                  sqlSelect := 'select '||chr(10)||chr(9)||self.standard_columns;
  7 
  8                  for i in 1..self.column_name.Count loop
  9                          sqlSelect := sqlSelect||chr(10)||chr(9)||','||
10                                  'sum( case when '||self.pivot_column||'='''||
11                                  self.column_values(i)||''' then 1 else 0 end ) as "'||
12                                  self.column_name(i)||'"';
13                  end loop;
14 
15                  sqlSelect := sqlSelect || chr(10)||'from '||self.table_name||chr(10)||
16                          'group by '||self.standard_columns||chr(10)||
17                          'order by '||self.order_by;
18 
19                  return( sqlSelect );
20          end;
21 
22          member function GetRefCursor return sys_refcursor is
23                  c sys_refcursor;
24          begin
25                  open c for self.GetSQL();
26                  return( c );
27          end;
28  end;
29  /
Type body created.
SQL> var c refcursor
SQL>
SQL> declare
  2          pivot   TDynamicPivot;
  3  begin
  4          pivot := new TDynamicPivot(
  5                          'emp', 'deptno', 'job',
  6                          '1',
  7                          TStringArray('ANALYST','CLERK','MANAGER','PRESIDENT','SALESMAN'),
  8                          TStringArray('ANALYST','CLERK','MANAGER','PRESIDENT','SALESMAN')
  9                  );
10          DBMS_OUTPUT.put_line( 'Pivot SQL:' );
11          DBMS_OUTPUT.put_line( pivot.GetSQL() );
12 
13          :c := pivot.GetRefCursor();
14  end;
15  /
Pivot SQL:
select
        deptno
        ,sum( case when job='ANALYST' then 1 else 0 end ) as "ANALYST"
        ,sum( case when job='CLERK' then 1 else 0 end ) as "CLERK"
        ,sum( case when job='MANAGER' then 1 else 0 end ) as "MANAGER"
        ,sum( case when job='PRESIDENT' then 1 else 0 end ) as "PRESIDENT"
        ,sum( case when job='SALESMAN' then 1 else 0 end ) as "SALESMAN"
from emp
group by deptno
order by 1
PL/SQL procedure successfully completed.
SQL>
SQL> print c
    DEPTNO    ANALYST      CLERK    MANAGER  PRESIDENT   SALESMAN
        10          0          1          1          1          0
        20          2          2          1          0          0
        30          0          1          1          0          4
SQL>
SQL>
SQL> with pivot as(
  2          select
  3                  TDynamicPivot(
  4                          'all_objects', 'owner', 'object_type',
  5                          '1',
  6                          TStringArray('TABLES','INDEXES','PROCEDURES'),
  7                          TStringArray('TABLE','INDEX','PROCEDURE')
  8                  )       as OBJECT
  9          from    dual
10  )
11  select
12          p.object.GetRefCursor() as "REFCURSOR",
13          p.object.GetSQL()       as "SQL"
14  from       pivot p;
REFCURSOR            SQL
CURSOR STATEMENT : 1 select
                        owner
                        ,sum( case when object_type='TABLE' then 1 else 0 end ) as "TABLES"
                        ,sum( case when object_type='INDEX' then 1 else 0 end ) as "INDEXES"
                        ,sum( case when object_type='PROCEDURE' then 1 else 0 end ) as "PROCEDURES"
                     from all_objects
                     group by owner
                     order by 1
CURSOR STATEMENT : 1
OWNER                              TABLES    INDEXES PROCEDURES
APEX_040100                             1          0         13
BILLY                                   4          2          3
CTXSYS                                  5          0          0
DBSNMP                                  0          0          0
EXFSYS                                  1          0          1
MDM                                    74          0          0
MDSYS                                  34          0          0
OLAPSYS                                 2          0          0
ORDDATA                                 0          0          0
ORDPLUGINS                              0          0          0
ORDSYS                                  0          0          7
PUBLIC                                  0          0          0
SYS                                    33          0         17
SYSTEM                                  7          0          0
TYPE                                    0          0          1
WMSYS                                   0          0          0
XDB                                    17          0          0
SQL>
SQL> with pivot as(
  2          select
  3                  TDynamicPivot(
  4                  'all_objects', 'owner', 'object_type',
  5                  '1',
  6                  cast( multiset(select distinct object_type from user_objects order by 1) as TStringArray ),
  7                  cast( multiset(select distinct object_type from user_objects order by 1) as TStringArray )
  8          )       as OBJECT
  9  from       dual
10  )
11  select
12          p.object.GetRefCursor() as "REFCURSOR",
13          p.object.GetSQL()       as "SQL"
14  from       pivot p;
REFCURSOR            SQL
CURSOR STATEMENT : 1 select
                        owner
                        ,sum( case when object_type='DATABASE LINK' then 1 else 0 end ) as "DATABASE LINK"
                        ,sum( case when object_type='FUNCTION' then 1 else 0 end ) as "FUNCTION"
                        ,sum( case when object_type='INDEX' then 1 else 0 end ) as "INDEX"
                        ,sum( case when object_type='PACKAGE' then 1 else 0 end ) as "PACKAGE"
                        ,sum( case when object_type='PACKAGE BODY' then 1 else 0 end ) as "PACKAGE BODY"
                        ,sum( case when object_type='PROCEDURE' then 1 else 0 end ) as "PROCEDURE"
                        ,sum( case when object_type='TABLE' then 1 else 0 end ) as "TABLE"
                        ,sum( case when object_type='TYPE' then 1 else 0 end ) as "TYPE"
                        ,sum( case when object_type='TYPE BODY' then 1 else 0 end ) as "TYPE BODY"
                     from all_objects
                     group by owner
                     order by 1
CURSOR STATEMENT : 1
OWNER                          DATABASE LINK   FUNCTION      INDEX    PACKAGE PACKAGE BODY  PROCEDURE      TABLE       TYPE  TYPE BODY
APEX_040100                                0          4          0         56            0         13          1          2          0
BILLY                                      0          1          2          1            1          3          4          8          4
CTXSYS                                     0          0          0         13            0          0          5          9          0
DBSNMP                                     0          0          0          1            0          0          0          0          0
EXFSYS                                     0          4          0          7            0          1          1         27          0
MDM                                        0          0          0          0            0          0         74          0          0
MDSYS                                      0         72          0         19            0          0         34        145          0
OLAPSYS                                    0          0          0          3            0          0          2          0          0
ORDDATA                                    0          0          0          0            0          0          0          0          0
ORDPLUGINS                                 0          0          0          5            0          0          0          0          0
ORDSYS                                     0         32          0         19            0          7          0        446          0
PUBLIC                                     0          0          0          0            0          0          0          0          0
SYS                                        0         86          0        226            0         17         33        762          0
SYSTEM                                     0          0          0          0            0          0          7          0          0
TYPE                                       0          0          0          0            0          1          0         14          0
WMSYS                                      0          4          0          6            0          0          0          8          0
XDB                                        0          5          0         28            0          0         17         90          0
SQL>
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