how to divide the columns in result of query in oracle database

问题

want to split the columns in result of query dynamically, how can i? i have three tables and joined them.to get the required columns.

select distinct t1.sal,t1.cat,t2.id,t3.shop 
from t_table1 t1,
 t_table2 t2,
 t_table3 t3,

where t1.sno=t2.sno AND
t2.cat=t3.cat
t3.dept_no=t3.dept_no

**output:**

t1.sal  t1.cat  t2.id  t3.shop  
1900    34R5     10     dense    
1900    34r5     10     SVM
1900    34r5     10     bpo
2345    3ER4     11     kpo
2345    3ER4     11     infra
12345   34F4     12     const

**desired output:**

t1.sal  t1.cat  t1.tin  t2.id  t3.shop_1   t3.shop_2  t3.shop_3 
 1900    34r5   23456       10     dense       svm         bpo
 2345    3er4   6543        11      kpo        infra       null
 12345   34f4   34556       12      const       null       null

回答1:

Use a PIVOT and the ROW_NUMBER analytic function:

SQL Fiddle

Oracle 11g R2 Schema Setup:

CREATE TABLE your_query_result (sal, cat, id, shop ) AS
SELECT 1900,   '34R5',   10,   'dense' FROM DUAL UNION ALL
SELECT 1900,   '34r5',   10,   'SVM' FROM DUAL UNION ALL
SELECT 1900,   '34r5',   10,   'bpo' FROM DUAL UNION ALL
SELECT 2345,   '3ER4',   11,   'kpo' FROM DUAL UNION ALL
SELECT 2345,   '3ER4',   11,   'infra' FROM DUAL UNION ALL
SELECT 12345,  '34F4',   12,   'const' FROM DUAL;

Query 1:

SELECT sal,
       cat,
       id,
       "1_SHOP" AS shop_1,
       "2_SHOP" AS shop_2,
       "3_SHOP" AS shop_3
FROM   (
  SELECT r.*,
         ROW_NUMBER() OVER (
           PARTITION BY sal, cat, id
           ORDER BY shop
         ) AS rn
  FROM   (
    SELECT * FROM your_query_result
  ) r
)
PIVOT (
  MAX( shop ) AS shop
  FOR rn IN ( 1, 2, 3 )
)

Results:

|   SAL |  CAT | ID | SHOP_1 | SHOP_2 | SHOP_3 |
|-------|------|----|--------|--------|--------|
|  1900 | 34R5 | 10 |  dense | (null) | (null) |
|  1900 | 34r5 | 10 |    SVM |    bpo | (null) |
|  2345 | 3ER4 | 11 |  infra |    kpo | (null) |
| 12345 | 34F4 | 12 |  const | (null) | (null) |

If you want the first and second rows on the same line then just change the CAT column to be in lower-case before generating the ROW_NUMBER and PIVOTing.

来源：https://stackoverflow.com/questions/51055826/how-to-divide-the-columns-in-result-of-query-in-oracle-database

标签

sql

Oracle

oracle11g