Hi,
In one of our application.One update query is doing lot of disk reads .It is using index but still it is slow.

Query:-

UPDATE REBOOKER SET REBOOK_CO='Y' WHERE RBK_ID=:B1

Explain plan is this:-
Rows Execution Plan
------- ---------------------------------------------------
0 UPDATE STATEMENT GOAL: CHOOSE
0 UPDATE OF 'REBOOKER'
0 INDEX GOAL: ANALYZED (RANGE SCAN) OF 'I_RBK_ID' (NON-UNIQUE)

Query is doing around 30831 disk reads for 123712 rows.
This columns contains lot of repeated values. Is non-unique index ok.

Anything else i need to do.

Thanks in advance :-)

Rgds
Parag