nếu bạn không có số cột động, bạn sẽ phải thực hiện phương pháp này và sử dụng một kiểu để giữ các cột (vì sql tĩnh có số lượng cột cố định).
SQL> create table my_table (cy_name varchar2(3), ca_date date, ca_value number);
Table created.
SQL> alter session set nls_date_format='mm/dd/yyyy';
Session altered.
SQL> insert into my_table
2 select 'CUL' cy_name, to_date('1/4/2013') ca_date, 12 ca_value from dual
3 union all
4 select 'CUL' cy_name, to_date('12/31/2012') ca_date, 12 ca_value from dual
5 union all
6 select 'CUL' cy_name, to_date('1/3/2013') ca_date, 12 ca_value from dual
7 union all
8 select 'CUR' cy_name, to_date('1/6/2013') ca_date, 12 ca_value from dual
9 union all
10 select 'CUR' cy_name, to_date('12/6/2013') ca_date, 12 ca_value from dual;
5 rows created.
SQL>
SQL> drop type colTab;
Type dropped.
SQL> drop type colType;
Type dropped.
SQL> create type colType as object (colname varchar2(30), value number);
2 /
Type created.
SQL> create type colTab as table of colType;
2 /
Type created.
SQL> alter session set nls_date_format='mm/dd/yyyy';
Session altered.
SQL> col val format a80
SQL> set linesize 90
SQL> select cy_name,
2 cast(multiset(select ca_date, ca_value
3 from my_table d
4 where d.cy_name = a.cy_name) as coltab) val
5 from my_table a
6 group by cy_name;
CY_ VAL(COLNAME, VALUE)
--- --------------------------------------------------------------------------------
CUR COLTAB(COLTYPE('01/06/2013', 12), COLTYPE('12/06/2013', 12))
CUL COLTAB(COLTYPE('01/04/2013', 12), COLTYPE('12/31/2012', 12), COLTYPE('01/03/2013
', 12))
hoặc tạo sql đầu tiên một cách động..ví dụ:
SQL> select 'select CY_NAME, ' from dual
2 union all
3 select case when rownum != 1 then ',' end || str
4 from (select distinct 'MAX(DECODE(CA_DATE, TO_DATE(''' || to_char(ca_date, 'dd-mm-yyyy') || ''', ''DD-MM-YYYY''), CA_VALUE, NULL)) as "' || to_char(ca_date, 'dd-mm-yyyy
') || '"' str
5 from my_table a)
6 union all
7 select 'FROM MY_TABLE
8 GROUP BY CY_NAME; ' from dual
9 ;
'SELECTCY_NAME,'
------------------------------------------------------------------------------------------
select CY_NAME,
MAX(DECODE(CA_DATE, TO_DATE('04-01-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "04-01-2013"
,MAX(DECODE(CA_DATE, TO_DATE('06-12-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "06-12-2013"
,MAX(DECODE(CA_DATE, TO_DATE('31-12-2012', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "31-12-2012"
,MAX(DECODE(CA_DATE, TO_DATE('03-01-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "03-01-2013"
,MAX(DECODE(CA_DATE, TO_DATE('06-01-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "06-01-2013"
FROM MY_TABLE
GROUP BY CY_NAME;
7 rows selected.
và chạy nó:
SQL> select CY_NAME,
2 MAX(DECODE(CA_DATE, TO_DATE('04-01-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "04-01-2013"
3 ,MAX(DECODE(CA_DATE, TO_DATE('06-12-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "06-12-2013"
4 ,MAX(DECODE(CA_DATE, TO_DATE('31-12-2012', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "31-12-2012"
5 ,MAX(DECODE(CA_DATE, TO_DATE('03-01-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "03-01-2013"
6 ,MAX(DECODE(CA_DATE, TO_DATE('06-01-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "06-01-2013"
7 FROM MY_TABLE
8 GROUP BY CY_NAME;
CY_ 04-01-2013 06-12-2013 31-12-2012 03-01-2013 06-01-2013
--- ---------- ---------- ---------- ---------- ----------
CUR 12 12
CUL 12 12 12
CẬP NHẬT cho bản chỉnh sửa của bạn:nếu số cols trong bản chỉnh sửa của bạn là 7:
SQL> select 'select CY_NAME, ' from dual
2 union all
3 select case when rownum != 1 then ',' end || str
4 from (select 'MAX(DECODE(CA_DATE, TO_DATE('''
5 || to_char((d-rownum+1), 'dd-mm-yyyy')
6 || ''', ''DD-MM-YYYY''), CA_VALUE, NULL)) as "'
7 || to_char((d-rownum+1), 'dd-mm-yyyy') || '"' str
8 from (select max(ca_date) d from cotton_arv) a
9 connect by level <= 7 /* change to the number of cols needed */)
10 union all
11 select 'FROM V_COTTON_ARV
12 GROUP BY CY_NAME; ' from dual
13 ;
'SELECTCY_NAME,'
------------------------------------------------------------------------------------------------
------------------------
select CY_NAME,
MAX(DECODE(CA_DATE, TO_DATE('04-01-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "04-01-2013"
,MAX(DECODE(CA_DATE, TO_DATE('03-01-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "03-01-2013"
,MAX(DECODE(CA_DATE, TO_DATE('02-01-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "02-01-2013"
,MAX(DECODE(CA_DATE, TO_DATE('01-01-2013', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "01-01-2013"
,MAX(DECODE(CA_DATE, TO_DATE('31-12-2012', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "31-12-2012"
,MAX(DECODE(CA_DATE, TO_DATE('30-12-2012', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "30-12-2012"
,MAX(DECODE(CA_DATE, TO_DATE('29-12-2012', 'DD-MM-YYYY'), CA_VALUE, NULL)) as "29-12-2012"
FROM V_COTTON_ARV
GROUP BY CY_NAME;