Using Rownum and ROwid returns duplicate records

Question

Hi All,
We have implemented pagination as below using rowid and rownum
SELECT
id
FROM
emp
WHERE
ROWID IN
SELECT RID FROM (SELECT
ROWID RID,
ROWNUM RNUM
FROM
SELECT ID FROM emp
WHERE
((T_ID IN (200005,200229,200230,200249,200250,200049))) AND
(dte >= sysdate-90) AND
(LOWER(DESC) = LOWER ('A') AND
LOWER(NVL(FLAG,'0')) != LOWER ('3') AND
LOWER(MODDE) like LOWER ('%210%')) ORDER BY dte ASC ))
WHERE ROWNUM < 11) WHERE RNUM>= 1)) ORDER BY dte emp.ASC
But, we face that - the query inserts duplicate records in consecutive pages. For Eg:
1.if a,b,c,d,e - is returned for first iteration, then for the next iteration - f,g,h,a,y is returned.
Is it because that the Order by clause doesnt have a Unique key column.
Please help. or suggest how to efficietly implement pagination without performance hit

Answer 1

try distinct since you are using only one column it will eliminate any duplicates.
SELECT distinct id
  FROM emp
WHERE (ROWID IN ( SELECT RID
                     FROM (SELECT ROWID RID,ROWNUM RNUM
                             FROM (SELECT ID
                                     FROM emp
                                    WHERE ((T_ID IN (200005,200229,200230,200249,200250,200049)))
                                      AND (dte >= sysdate-90)
                                      AND (LOWER(DESC) = LOWER ('A')
                                      AND LOWER(NVL(FLAG,'0')) != LOWER ('3')
                                      AND LOWER(MODDE) like LOWER ('%210%'))
                                   ORDER BY dte ASC ))
                            WHERE ROWNUM < 11) 
                    WHERE RNUM>= 1))
ORDER BY dte emp.ASC