SQL & PL/SQL

Dear all,
I need to select certain dates and following days with the same criteria.
An example would be:

CREATE TABLE DEMO
(
EMP_ID NUMBER NOT NULL,
WORKING_DAY DATE NOT NULL,
ACTIVE_CODE VARCHAR2 (1) NULL,
CONSTRAINT DEMO_PK
PRIMARY KEY(EMP_ID, WORKING_DAY)
USING INDEX
)


INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('01.11.2010 00:00:00'), '_');
INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('02.11.2010 00:00:00'), '_');
INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('03.11.2010 00:00:00'), 'K');
INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('04.11.2010 00:00:00'), 'K');
INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('05.11.2010 00:00:00'), 'K');
INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('06.11.2010 00:00:00'), NULL);
INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('07.11.2010 00:00:00'), NULL);
INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('08.11.2010 00:00:00'), 'K');
INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('09.11.2010 00:00:00'), '_');
INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('10.11.2010 00:00:00'), 'K');
INSERT INTO DEMO( EMP_ID, WORKING_DAY, ACTIVE_CODE) VALUES( 123, TO_DATE('11.11.2010 00:00:00'), '_');

Now I'm looking for the first day with Active_Code ='K' and want to count the following days that have 'K', too.
Expected result: November 3rd -> 4 Ks (because the 8th is after the weekend); November 10th -> 1K

I hope the example/explanation isn't too bad...

I have built a procedure that would do the counting of the following occurances, if I give the first occurance (here 3rd and 8th).
But findign the first 'K' is my problem.
One solution would be:
AND
(SELECT T2.ACTIVE_CODE FROM DEMO T2
WHERE T2.EMP_ID= T1.EMP_ID AND T2.WORKING_DAY= T1.WORKING_DAY-1) <> 'K'
AND
(SELECT T2.ACTIVE_CODE FROM DEMO T2
WHERE T2.EMP_ID= T1.EMP_ID AND T2.WORKING_DAY= T1.WORKING_DAY-2) <> 'K'
AND
(SELECT T2.ACTIVE_CODE FROM DEMO T2
WHERE T2.EMP_ID= T1.EMP_ID AND T2.WORKING_DAY= T1.WORKING_DAY-3) <> 'K'

But it's damn imperformant if I'm dealing with millions of records :-(

Could anyone please give me a hint on how to solve this?
Thank you.

Best Regards
Christian