SQL Query : Order By issue with HUGE Table

Question

Hello friends,
I have been through a terrible issue with order by. I would appreciate your help. Please let me know, your input for my case:
=> if i run select query it returns result quick in some milliseconds. (sql dev. fetches 50 rows at a time)
=> if i run select query with where condition and column (say A) in where condition is even indexed and i have order by and that order by column (say B) is also indexed.
Now, here is the issue:
1. if no. of rows with that where condition can filter yielding small result set then order by works fine .. 1-5 sec which is good.
2.*if no. of rows with that where condition can filter yielding Large result set, say more than 50,000 then with order by then the wait time is exponential.... i have even waited 10+ mins to get the result back for 120,000 records.*
Is order by takes that long for 100K records ... i think something else if wrong... your pointer will really be helpful... i am very new to sql and even newer for large table case.
I am using SQL Developer Version 2.1.1.64
and Oracle Database 11g Enterprise Edition Release 11.1.0.7.0 - 64bit Production
Thank you so much.
Edited by: 896719 on Jan 11, 2013 8:38 AM

Answer 1

Yes you are correct, but my concentration was on order by thing, so it will do full scan of table so i was putting that ... and was also wondering if millions of record in table should not be a issue...???
Any way for the explain plan , when just a value in the where changes there is the huge difference i want to point out too as below:
SELECT
FROM
    EES_EVT EES_EVT  where APLC_EVT_CD= 'ABC' ORDER BY  CRE_DTTM DESC
execution time : 0.047 sec
Plan hash value: 290548126
| Id  | Operation                    | Name        | Rows  | Bytes | Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT             |             |    27 | 14688 |    25   (4)| 00:00:01 |
|   1 |  SORT ORDER BY               |             |    27 | 14688 |    25   (4)| 00:00:01 |
|   2 |   TABLE ACCESS BY INDEX ROWID| EES_EVT     |    27 | 14688 |    24   (0)| 00:00:01 |
|*  3 |    INDEX RANGE SCAN          | XIE1EES_EVT |    27 |       |     4   (0)| 00:00:01 |
Predicate Information (identified by operation id):
   3 - access("APLC_EVT_CD"='ABC')
Note
   - SQL plan baseline "SYS_SQL_PLAN_6d41e6b91925c463" used for this statement
=============================================================================================
SELECT
FROM
    EES_EVT EES_EVT  where APLC_EVT_CD= 'XYZ' ORDER BY  CRE_DTTM DESC
execution : 898.672 sec.
Plan hash value: 290548126
| Id  | Operation                    | Name        | Rows  | Bytes |TempSpc| Cost (%CPU)| Time     |
|   0 | SELECT STATEMENT             |             |   121K|    62M|       |   102K  (1)| 00:11:02 |
|   1 |  SORT ORDER BY               |             |   121K|    62M|    72M|   102K  (1)| 00:11:02 |
|   2 |   TABLE ACCESS BY INDEX ROWID| EES_EVT     |   121K|    62M|       | 88028   (1)| 00:09:27 |
|*  3 |    INDEX RANGE SCAN          | XIE1EES_EVT |   121K|       |       |   689   (1)| 00:00:05 |
Predicate Information (identified by operation id):
   3 - access("APLC_EVT_CD"='XYZ')
Note
   - SQL plan baseline "SYS_SQL_PLAN_ef5709641925c463" used for this statementAlso Note this table contains 74328 MB data in it.
Thanks