Oracle11g, Multiple Pivots - sql

Question

So I have a working query that pivots some data for me.
SELECT * FROM (
select requisitions.ACC_ID AS "Accession #"
,tests.TEST_ID
,results.RESULT_NUMERIC
FROM requisitions
inner join req_panels ON requisitions.acc_id = req_panels.acc_id
inner join results ON req_panels.rp_id = results.rp_id
inner join tests ON results.test_id = tests.test_id
WHERE results.TEST_ID IN (1,2,3,4)
AND requisitions.RECEIVED_DATE > TO_DATE('9/1/2013', 'MM/DD/YYYY')
ORDER BY requisitions.ACC_ID
)
pivot(
MAX(RESULT_NUMERIC)
for TEST_ID IN ('1' AS Test1,'2' AS Test2,'3' AS Test3,'4' AS Test4)
)
Now, I have to include a different type of result (RESULTS_ALPHA in results table) as a column for each ACC_ID. RESULT_ALPHA is a clob. For the test_id's already included in the code above RESULTS_ALPHA is empty. But it holds a value for another test, we'll call it "TestAlpha".
So what I have currently output from the code above is;
Acc_ID | Test 1 | Test 2 | Test 3 | Test 4
-------------------------------------------
000001 | 24 | 1.5 | 0.5 | 2.1
000002 | 15 | 2.1 | 0.3 | 1.3
And I need to get
Acc_ID | Test 1 | Test 2 | Test 3 | Test 4 | TestAlpha
--------------------------------------------------------
000001 | 24 | 1.5 | 0.5 | 2.1 | abcd
000002 | 15 | 2.1 | 0.3 | 1.3 | efgh
How can I accomplish this? Another pivot?
Thanks.

Answer 1

If you can use just the first 4000 characters of a CLOB field then you can just substring it:
SELECT * FROM (
select requisitions.ACC_ID AS "Accession #"
,tests.TEST_ID
,results.RESULT_NUMERIC
,dbms_lob.substr(results.RESULT_ALPHA, 4000, 1) as result_alpha
FROM requisitions
...
Of course that gives you a 4000-character-wide column in your output, but not much you can do about that really, unless you can set a lower length based on knowledge of what's in the column. (Though if it's less than 4K, it doesn't really make sense to store it as a CLOB; sounds like you have a mix of data in there though).
Even if the value is more than 4000 characters this will show the start of it. Whether that's acceptable, or useful, depends what you're doing with the result of the pivot.
What you're doing does seem to assume that the RESULTS_ALPHA is the same for all results records for each TEST_ID; or even for each ACC_ID. Which seems a bit wasteful if it's true.
I'm not sure if there a non-programmatic solution to get the full CLOB back.