Bạn cần sử dụng PIVOT tiêu chuẩn truy vấn.
Tùy thuộc vào phiên bản cơ sở dữ liệu Oracle của bạn , bạn có thể làm điều đó theo hai cách:
Sử dụng PIVOT cho phiên bản 11g trở lên:
SQL> SELECT *
2 FROM
3 (SELECT c.place place,
4 row_number() OVER(PARTITION BY c.place ORDER BY NULL) cnt,
5 (row_number() OVER(PARTITION BY c.place ORDER BY NULL)/
6 COUNT(place) OVER(ORDER BY NULL))*100 pct
7 FROM person_injuryPlace_map A
8 JOIN person b
9 ON(A.person_id = b.ID)
10 JOIN injury_place c
11 ON(A.injury_id = c.ID)
12 ORDER BY c.place
13 ) PIVOT (MAX(cnt),
14 MAX(pct) pct
15 FOR (place) IN ('kitchen' AS kitchen,
16 'Washroom' AS Washroom,
17 'Rooftop' AS Rooftop,
18 'Garden' AS Garden));
KITCHEN KITCHEN_PCT WASHROOM WASHROOM_PCT ROOFTOP ROOFTOP_PCT GARDEN GARDEN_PCT
---------- ----------- ---------- ------------ ---------- ----------- ---------- ----------
1 14.2857143 3 42.8571429 1 14.2857143 2 28.5714286
Sử dụng MAX và DECODE cho phiên bản 10g và trước đây:
SQL> SELECT MAX(DECODE(t.place,'kitchen',cnt)) Kitchen ,
2 MAX(DECODE(t.place,'kitchen',pct)) Pct ,
3 MAX(DECODE(t.place,'Washroom',cnt)) Washroom ,
4 MAX(DECODE(t.place,'Washroom',pct)) Pct ,
5 MAX(DECODE(t.place,'Rooftop',cnt)) Rooftop ,
6 MAX(DECODE(t.place,'Rooftop',pct)) Pct ,
7 MAX(DECODE(t.place,'Garden',cnt)) Garden ,
8 MAX(DECODE(t.place,'Garden',pct)) Pct
9 FROM
10 (SELECT b.ID bid,
11 b.NAME NAME,
12 c.ID cid,
13 c.place place,
14 row_number() OVER(PARTITION BY c.place ORDER BY NULL) cnt,
15 ROUND((row_number() OVER(PARTITION BY c.place ORDER BY NULL)/
16 COUNT(place) OVER(ORDER BY NULL))*100, 2) pct
17 FROM person_injuryPlace_map A
18 JOIN person b
19 ON(A.person_id = b.ID)
20 JOIN injury_place c
21 ON(A.injury_id = c.ID)
22 ORDER BY c.place
23 ) t;
KITCHEN PCT WASHROOM PCT ROOFTOP PCT GARDEN PCT
---------- ---------- ---------- ---------- ---------- ---------- ---------- ----------
1 14.29 3 42.86 1 14.29 2 28.57
