automatic undo mysteries

Hi,

Please look at the alert log error I got

It shows ORA-01555 but the query duration is 0 seconds. How is that possible that query goe the error just after starting

this is Oracle 9.2.0.5 running with automatic undo with undo_retention = 36000

ORA-01555 caused by SQL statement below (Query Duration=0 sec, SCN: 0x000c.46f0197a):
Sat Nov 26 01:01:32 2005
SELECT
"EFFECTIVE_START_DATE","EFFECTIVE_END_DATE","POSITION_ID","ASSIGNMENT_STATUS_TYPE_ID","PERSON_ID","ORGANIZATION_ID","ASS_ATTRIBUTE9","A SS_ATTRIBUTE16" FROM "HR"."PER_ALL_ASSIGNMENTS_F" "AL1" WHERE "EFFECTIVE_END_DATE">=:1 AND "EFFECTIVE_START_DATE"<=:2 AND "ASS_ATTRIBUTE9" LIK
E 'CRN%' AND
(TO_DATE(SUBSTR("ASS_ATTRIBUTE16",1,10),'YYYY/MM/DD')>TO_DATE('16-FEB-'||TO_CHAR(:3,'YYYY'),'DD-MON-YYYY') AND TO_DATE(SUBSTR("AS
S_ATTRIBUTE16",1,10),'YYYY/MM/DD')<=TO_DATE('31-MAY-'||TO_CHAR(:4,'YYYY'),'DD-MON-YYYY') OR TO_DATE(SUBSTR("ASS_ATTRIBUTE16",1,10),'YYYY/MM/DD
')>TO_DATE('01-OCT-'||TO_CHAR(:5,'YYYY'),'DD-MON-YYYY') AND
TO_DATE(SUBSTR("ASS_ATTRIBUTE16",1,10),'YYYY/MM/DD')<=TO_DATE('15-JAN-'||TO_CHAR(T O_NUMBER(TO_CHAR(:6,'YYYY'))+1),'DD-MON-YYYY')) Sat Nov 26 01:31:30 2005

I also checked stats$undostat that shows ssolderrcnt as 1 for the time interval

but it shows 0 for both for all others block resue and steal counts.

So why is the query getting snapshot tool old.

Could any out guys could clarify my confustion

thanks
amit

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