Env : DB2 9.5 / AIX 5.3

I noticed that couple of agents (which has more CPU usage) has the following information on application snapshot

Rows selected = 1022020398
Rows read = 5280
Rows written = 645


But I am not sure how is it possible as rows selected(fetched) is a subset of rows read.

Other related info from the same app snap is as below
Application handle = 8040
Application status = UOW Waiting
Status change time = 10/28/2010 11:43:39.075514
Application code page = 1208
Binds/precompiles attempted = 0
Rows deleted = 0
Rows inserted = 186
Rows updated = 461
Rows selected = 1022020398
Rows read = 5280
Rows written = 645
Most recent operation = Close
Cursor name = SQL_CURSH100C4
Most recent operation start timestamp = 10/28/2010 11:43:39.075150
Most recent operation stop timestamp = 10/28/2010 11:43:39.075493


Pls advice

I suspect DB2 is most likely doing an index-only to get most of the rows.