How to optimize oracle query? - oracle

Question

Following query is taking around 45 seconds in oracle 11g
select count(cap.ISHIGH),ms.SID,ms.NUM from CDetail cap,MData ms
where cap.MDataID_FK=ms.MDataID_PK and trunc(cap.CREATEDTIME) between trunc(sysdate-10) and trunc(sysdate)
group by ms.SID,ms.NUM ;
explain plan :
-------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes |TempSpc| Cost (%CPU)| Time |
-------------------------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 766K| 32M| | 94421 (1)| 00:18:54 |
| 1 | HASH GROUP BY | | 766K| 32M| 41M| 94421 (1)| 00:18:54 |
|* 2 | HASH JOIN | | 766K| 32M| 21M| 85716 (1)| 00:17:09 |
| 3 | VIEW | VW_GBC_5 | 766K| 13M| | 73348 (1)| 00:14:41 |
| 4 | HASH GROUP BY | | 766K| 13M| 98M| 73348 (1)| 00:14:41 |
|* 5 | FILTER | | | | | | |
| 6 | TABLE ACCESS BY INDEX ROWID| CDetail | 3217K| 58M| | 63738 (1)| 00:12:45 |
|* 7 | INDEX RANGE SCAN | IDX_CPCTYDTLTRNCCRTDTM | 3365K| | | 14679 (1)| 00:02:57 |
| 8 | TABLE ACCESS FULL | MData | 871K| 22M| | 9665 (1)| 00:01:56 |
-------------------------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ITEM_1"="MS"."MDataID_PK")
5 - filter(TRUNC(SYSDATE#!-10)<=TRUNC(SYSDATE#!))
7 - access(TRUNC(INTERNAL_FUNCTION("CREATEDTIME"))>=TRUNC(SYSDATE#!-10) AND
TRUNC(INTERNAL_FUNCTION("CREATEDTIME"))<=TRUNC(SYSDATE#!))
table MData contains around 900,000 rows and table CDetail contains 23,000,000 rows.
Should I introduce any new index or any other way to optimize the above query.
Edit 3. IDX_CPCTYDTLTRNCCRTDTM is a functional index on trunc(CREATEDTIME)
Edit :1
explain plan :for full table scan using hint /+full(Cdetail)/
---------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes |TempSpc| Cost (%CPU)| Time |
---------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 780K| 33M| | 160K (2)| 00:32:01 |
| 1 | HASH GROUP BY | | 780K| 33M| 42M| 160K (2)| 00:32:01 |
|* 2 | HASH JOIN | | 780K| 33M| 22M| 151K (2)| 00:30:15 |
| 3 | VIEW | VW_GBC_5 | 780K| 13M| | 138K (2)| 00:27:46 |
| 4 | HASH GROUP BY | | 780K| 14M| 230M| 138K (2)| 00:27:46 |
|* 5 | FILTER | | | | | | |
|* 6 | TABLE ACCESS FULL| CDetail | 7521K| 136M| | 120K (2)| 00:24:02 |
| 7 | TABLE ACCESS FULL | MData | 890K| 22M| | 9666 (1)| 00:01:56 |
---------------------------------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
2 - access("ITEM_1"="MS"."MDataID_PK")
5 - filter(TRUNC(SYSDATE#!-10)<=TRUNC(SYSDATE#!))
6 - filter(TRUNC(INTERNAL_FUNCTION("CREATEDTIME"))>=TRUNC(SYSDATE#!-10) AND
TRUNC(INTERNAL_FUNCTION("CREATEDTIME"))<=TRUNC(SYSDATE#!))

Answer 1

Thank you for sharing an explain plan; thats a good start. The thing with an explain plan however is that it gives you estimates, not actuals. If you can, can you get a SQL Monitor report? This will show you the actual cardinality and show you where time is being spent in the query.
The date filter is expecting about 3M rows (ID's 6 an 7)? Is that accurate?
What is the definition of the IDX_CPCTYDTLTRNCCRTDTM index? Does it happen to be function based?
Just to validate my thinking, can you add the following hint, run the query and get the explain plan again.
select /*+ full( cap ) */ ...