IP17 Upgrade - Cancelling Upgrep

Upgrep seems to run for a long time

DBA says that it seems to load millions of records due to the IN clause and is causing great amount of delay (this query seems to be running for more than 6 hours now)

20 million records in activities in our systems. 

UPDATE S_EVT_ACT_CAL

   SET TIME_ZONE_NAME =

(SELECT S_TIMEZONE.NAME

FROM S_TIMEZONE, S_CONTACT, S_EVT_ACT

WHERE S_EVT_ACT_CAL.PAR_ROW_ID = S_EVT_ACT.ROW_ID

AND S_CONTACT.ROW_ID = S_EVT_ACT.OWNER_PER_ID

AND S_TIMEZONE.ROW_ID = S_CONTACT.TIMEZONE_ID)