oracle sql field from cross reference table

Question

i am novice at SQL and have problems hope you can help me :

ORACLE 10g

table ACCOUNT

+----------+----------+
| ACCOUNTID| LBKEY    |
+----------+----------+
|      ... | ...      |
|      254 | value254 |
|      ... | ...      |
|      401 | value401 |
|      ... | ...      |
|      405 | value405 |
+----------+----------+

cross reference table

+----------+----------+----------+--------+
| IDTABLE2 | ACCOUNTID|  OIDID   | VALUE  |
+----------+----------+----------+--------+
|      ... | ...      | ...      | ...    |
|      475 | 401      | 4        | 40000  |
|      476 | 405      | 4        | 35000  |
|       ...| ...      | ...      | ...    |
|     3000 | 254      | 5        | PARIS  |
|     3001 | 401      | 5        | LONDON |
|     3002 | 405      | 5        | SYDNEY |
|       ...| ...      | ...      | ...    |
+----------+----------+----------+--------+

table OID

+----------+-------------+-------------+
| OIDID    |     OID     | DESCRIPTION |
+----------+-------------+-------------+
|        1 | x           | x           |
|        2 | x           | x           |
|        3 | x           | x           |
|        4 | 1.3.6.1.4.1 | Post Code   |
|        5 | 1.3.6.1.4.2 | City        |
|        6 | x           | x           |
|        7 | x           | x           |
|        8 | x           | x           |
|        9 | x           | x           |
|       10 | x           | x           |
+----------+-------------+-------------+

Expected result

Constraint : all the ACCOUNT (LBKEY) who has one postal code(OID 4) or city code(OID 5) in the cross reference table

+----------+-------------+-------------+
| LBKEY    |  POST CODE  |  CITY       |
+----------+-------------+-------------+
| value254 | null        | PARIS       |
| value401 | 40000       | LONDON      |
| value405 | 35000       | SYDNEY      |
+----------+-------------+-------------+

Answer 1

Three different ways of doing it:

SQL Fiddle

Oracle 11g R2 Schema Setup:

CREATE TABLE ACCOUNT ( ACCOUNTID, LBKEY ) AS
          SELECT 254, 'value254' FROM DUAL
UNION ALL SELECT 401, 'value401' FROM DUAL
UNION ALL SELECT 405, 'value405' FROM DUAL
UNION ALL SELECT 406, 'value406' FROM DUAL;

CREATE TABLE CrossReference ( IDTABLE2, ACCOUNTID, OIDID, VALUE ) AS
          SELECT  475, 401, 4, '40000' FROM DUAL
UNION ALL SELECT  476, 405, 4, '35000' FROM DUAL
UNION ALL SELECT 3000, 254, 5, 'PARIS' FROM DUAL
UNION ALL SELECT 3001, 401, 5, 'LONDON' FROM DUAL
UNION ALL SELECT 3002, 405, 5, 'SYDNEY' FROM DUAL
UNION ALL SELECT 4000, 406, 6, 'x' FROM DUAL;


CREATE TABLE OID (OIDID, OID, DESCRIPTION ) AS
          SELECT  1, 'x', 'x' FROM DUAL
UNION ALL SELECT  2, 'x', 'x' FROM DUAL
UNION ALL SELECT  3, 'x', 'x' FROM DUAL
UNION ALL SELECT  4, '1.3.6.1.4.1', 'Post Code' FROM DUAL
UNION ALL SELECT  5, '1.3.6.1.4.2', 'City' FROM DUAL
UNION ALL SELECT  6, 'x', 'x' FROM DUAL
UNION ALL SELECT  7, 'x', 'x' FROM DUAL
UNION ALL SELECT  8, 'x', 'x' FROM DUAL
UNION ALL SELECT  9, 'x', 'x' FROM DUAL
UNION ALL SELECT 10, 'x', 'x' FROM DUAL;

Query 1:

SELECT LBKEY,
       MAX( CASE OIDID WHEN 4 THEN VALUE END ) AS "Post Code",
       MAX( CASE OIDID WHEN 5 THEN VALUE END ) AS "City"
FROM   ACCOUNT a
       INNER JOIN
       CrossReference c
       ON ( a.ACCOUNTID = c.ACCOUNTID )
WHERE  c.OIDID IN ( 4, 5 )
GROUP BY LBKEY

Results:

|    LBKEY | POST CODE |   CITY |
|----------|-----------|--------|
| value254 |    (null) |  PARIS |
| value405 |     35000 | SYDNEY |
| value401 |     40000 | LONDON |

Query 2:

WITH data AS (
  SELECT LBKEY,
         ( SELECT VALUE
           FROM   CrossReference c
           WHERE  c.ACCOUNTID = a.ACCOUNTID
           AND    c.OIDID = 4 ) AS "Post Code",
         ( SELECT VALUE
           FROM   CrossReference c
           WHERE  c.ACCOUNTID = a.ACCOUNTID
           AND    c.OIDID = 5 ) AS "City"
  FROM   ACCOUNT a
)
SELECT *
FROM   data
WHERE  "Post Code" IS NOT NULL
OR     "City"      IS NOT NULL

Results:

|    LBKEY | POST CODE |   CITY |
|----------|-----------|--------|
| value254 |    (null) |  PARIS |
| value401 |     40000 | LONDON |
| value405 |     35000 | SYDNEY |

Query 3:

SELECT LBKEY,
       c1.VALUE AS "Post Code",
       c2.VALUE AS City
FROM   ACCOUNT a
       LEFT OUTER JOIN
       ( SELECT ACCOUNTID, VALUE FROM CrossReference WHERE OIDID = 4 ) c1
       ON ( c1.ACCOUNTID = a.ACCOUNTID )
       LEFT OUTER JOIN
       ( SELECT ACCOUNTID, VALUE FROM CrossReference WHERE OIDID = 5 ) c2
       ON ( c2.ACCOUNTID = a.ACCOUNTID )
WHERE  c1.VALUE IS NOT NULL
OR     c2.VALUE IS NOT NULL

Results:

|    LBKEY | POST CODE |   CITY |
|----------|-----------|--------|
| value254 |    (null) |  PARIS |
| value401 |     40000 | LONDON |
| value405 |     35000 | SYDNEY |

Answer 2

I think this could work for you:

select
        lbkey,
        cross_post.value as postcode,
        cross_city.value as city
from
        ACCOUNT a,
        cross cross_city,
        cross cross_post,
where
        a.accountid=cross_city.accountid(+) and
        a.accountid=cross_post.accountid(+) and
        nvl(cross_city.oidid,5)=5 and
        nvl(cross_post.oidid,4)=4 and
        (cross_city.oidid is not null or cross_post.oidid is not null)