Question : Possible repair of HP Storageworks SDLT 600

I have an HP Storageworks SDLT 600 tape drive. The orange light (indicating it needs cleaning) came on the other night and won't go away even after multiple cleanings. So, I ran the HP tape library tools utility device assessment test. It failed due to too many read/write errors and said the device should be exchanged (replaced).

Everything else on the drive seems to work fine (inserting/ejecting tapes, etc.). I was wondering if replacing the tape drive "head" could possibly fix this problem? Also, would someone be able to recommend where I could purchase the part and get instructions for replacing the part?
Thank you for your help and advice.

Answer : Possible repair of HP Storageworks SDLT 600

Sub queries can only be used in SQL statements.  Since this case statement is in PL/SQL not regular SQL, you cannot do it.

Either select the id into another variable or somehow join the selects into a single select statement ot return the desired type_id.

What does the following return:

SELECT   WAVELENGTH_TYPE_ID
              INTO   P_WAVELENGTH_TYPE_ID
              FROM   LAYER1_WAVELENGTH_TYPE
             WHERE   WAVELENGHT_TYPE_NAME = TDP_LOAD_SUMMARY_REC.Customer and
TDP_LOAD_SUMMARY_REC.Customer IN
                      ('CNI-CD',
                       'CNI-00',
                       'CNI-TC',
                       'CNI-M',
                       'CNI-RH',
                       'CNI-XC',
                       'CNI-NP',
                       'CNI-RT')
and
P_PROGRAM_ID IN (SELECT   PROGRAM_ID FROM   LAYER1_PROGRAM WHERE PROGRAM = 'MSP/DMX');