New column based on the value of another column | Oracle? - sql

Question

In an Oracle 11g database I have table called organizations which looks like this:
| ORGANIZATION_ID | ORGANIZATION_NAME | TREE_ORGANIZATION_ID | ORGANIZATION_RANG |
|-----------------|-------------------|----------------------|-------------------|
| 1 | Facebook | \1 | 1 |
| 2 | Instagram | \1\2 | 2 |
| 3 | Whatsapp | \1\3 | 2 |
| 4 | Alphabet | \4 | 1 |
| 5 | Nest | \4\5 | 2 |
| 6 | Google | \4\6 | 2 |
| 7 | YouTube | \4\6\7 | 3 |
As you can see this table has column called TREE_ORGANIZATION_ID where I store information about relationship of organizations.
This code returns all organizations that have a specific ID in the column TREE_ORGANIZATION_ID. In my case this code return Google and YouTube entries.
SELECT
*
FROM
ORGANIZATIONS
WHERE
TREE_ORGANIZATION_ID LIKE '%\' || '6'
OR
TREE_ORGANIZATION_ID LIKE '%\' || '6' || '\%';
I want to add new column called STATUS which looks like this:
| ORGANIZATION_ID | ORGANIZATION_NAME | TREE_ORGANIZATION_ID | ORGANIZATION_RANG | STATUS |
|-----------------|-------------------|----------------------|-------------------|----------|
| 6 | Google | \4\6 | 2 | root |
| 7 | YouTube | \4\6\7 | 3 | not root |
I tried next code but it raise error ORA-00937 not a single-group group function.
How do I create a new column based on the value of another column?
SELECT
ORGANIZATION_ID,
ORGANIZATION_NAME,
TREE_ORGANIZATION_ID,
CASE
WHEN ORGANIZATION_RANG = MIN(ORGANIZATION_RANG) THEN 'root'
ELSE 'not root'
END AS STATUS
FROM
ORGANIZATIONS
WHERE
TREE_ORGANIZATION_ID LIKE '%\' || '6'
OR
TREE_ORGANIZATION_ID LIKE '%\' || '6' || '\%';

Answer 1

You can try below -
SELECT
ORGANIZATION_ID,
ORGANIZATION_NAME,
TREE_ORGANIZATION_ID,
CASE
WHEN TREE_ORGANIZATION_ID LIKE '%\' || '6' THEN 'root'
when TREE_ORGANIZATION_ID LIKE '%\' || '6' || '\%' then 'not root'
END AS STATUS
FROM
ORGANIZATIONS
WHERE
TREE_ORGANIZATION_ID LIKE '%\' || '6'
OR
TREE_ORGANIZATION_ID LIKE '%\' || '6' || '\%'

Answer 2

You want to use an analytic function, not an aggregation function:
SELECT ORGANIZATION_ID, ORGANIZATION_NAME, TREE_ORGANIZATION_ID,
(CASE WHEN ORGANIZATION_RANG = MIN(ORGANIZATION_RANG) OVER ()
THEN 'root'
ELSE 'not root'
END) AS STATUS
FROM ORGANIZATIONS O
WHERE TREE_ORGANIZATION_ID || '\' LIKE '%\' || '6' || '\%';
Note that this also simplifies the logic for matching 6 by testing the organization id with a backslash on the end. You could also use REGEXP_LIKE() for this purpose.