Re: Query Execution Time
Date: Mon, 17 Nov 2008 22:36:33 -0800 (PST)
Message-ID: <19694397-c443-4c10-9e98-8c77584685e9@k36g2000pri.googlegroups.com>
Hi,
This mail is regarding the explain plan output, I have the following
doubts, Please clarify them :
1.
In the below explain plan, what does the rows column here mean.
Should we have the exact number of rows in our query output as present
here ?
(In most cases, i dont have the query output same as the Rows column,
is that correct ? )
2. For good performance, do we have to check the plan or the execution
time.
I am asking this, Because, i found that the plan is good in some
cases, but the execution time is more.
Any suggestions on this ?
3. What is the Bytes column ?
Does the Bytes in column changes for the 2nd or 3rd execution of the same query ?
| Id | Operation |
Name | Rows | Bytes | Cost (%CPU)| Time
|
| 0 | SELECT STATEMENT
| | 1 | 307 | 5 (20)|
00:00:01 |
|* 1 | MAT_VIEW ACCESS BY INDEX ROWID |
CODE_VALUES | 16 | 1232 | 1 (0)| 00:00:01
|
| 2 | NESTED LOOPS
| | 8 | 840 | 3 (0)|
00:00:01 |
| 3 | NESTED LOOPS
| | 1 | 28 | 2 (0)|
00:00:01 |
| 4 | MAT_VIEW ACCESS BY INDEX ROWID |
PWM_SECURITY_CLASSIFICATION | 1 | 7 | 1 (0)| 00:00:01
|
|* 5 | INDEX UNIQUE SCAN |
SYS_C0021372 | 1 | | 1 (0)| 00:00:01
|
| 6 | MAT_VIEW ACCESS BY INDEX ROWID |
CODES | 1 | 21 | 1 (0)| 00:00:01
|
|* 7 | INDEX RANGE SCAN |
IDX_TB_CODES_SRTDESC | 1 | | 1 (0)| 00:00:01
|
|* 8 | INDEX RANGE SCAN |
IDX_TB_CODE_VALUES_CODEINST | 113 | | 1 (0)| 00:00:01
|
| 9 | SORT GROUP BY
| | 1 | 307 | 5 (20)|
00:00:01 |
|* 10 | FILTER
| | | |
| |
| 11 | NESTED LOOPS
| | 1 | 307 | 4 (0)|
00:00:01 |
| 12 | NESTED LOOPS
| | 1 | 265 | 3 (0)|
00:00:01 |
| 13 | NESTED LOOPS
| | 1 | 72 | 2 (0)|
00:00:01 |
|* 14 | INDEX RANGE SCAN |
IDX_MV_ACCT_GRP_UIN_GID_EID_PC | 1 | 19 | 1 (0)| 00:00:01
|
| 15 | MAT_VIEW ACCESS BY INDEX ROWID |
PWM_POSITION_PARTNERSHIP_MV2 | 13 | 689 | 1 (0)| 00:00:01
|
|* 16 | INDEX RANGE SCAN |
IDX_POS_PART_PI_TS_EI_ED_SA2 | 13 | | 1 (0)| 00:00:01
|
|* 17 | MAT_VIEW ACCESS BY INDEX ROWID |
SECURITY_MASTER | 1 | 193 | 1 (0)| 00:00:01
|
|* 18 | INDEX UNIQUE SCAN |
PK_SECURITY_MASTER | 1 | | 1 (0)| 00:00:01
|
| 19 | MAT_VIEW ACCESS BY INDEX ROWID |
ENTITY | 1 | 42 | 1 (0)| 00:00:01
|
|* 20 | INDEX UNIQUE SCAN |
PK_ENTITY | 1 | | 1 (0)| 00:00:01
|
|* 21 | INDEX UNIQUE SCAN |
SYS_C0021359 | 1 | 9 | 1 (0)| 00:00:01
|
| 22 | NESTED LOOPS
| | 1 | 74 | 4 (0)|
00:00:01 |
| 23 | NESTED LOOPS
| | 1 | 49 | 3 (0)|
00:00:01 |
| 24 | NESTED LOOPS
| | 1 | 32 | 2 (0)|
00:00:01 |
| 25 | MAT_VIEW ACCESS BY INDEX ROWID|
PWM_PARTNERSHIP_XREF | 1 | 13 | 1 (0)| 00:00:01
|
|* 26 | INDEX UNIQUE SCAN |
SYS_C0021359 | 1 | | 1 (0)| 00:00:01
|
|* 27 | INDEX RANGE SCAN |
IDX_MV_ACCT_GRP_UIN_GID_EID_P3 | 1 | 19 | 1 (0)| 00:00:01
|
|* 28 | INDEX RANGE SCAN |
IDX_TB_PAAOD_EID_AOD | 1 | 17 | 1 (0)| 00:00:01
|
|* 29 | INDEX RANGE SCAN |
SYS_C0021159 | 1 | 25 | 1 (0)| 00:00:01
|
Thanks in Advance.
With Regards,
Raja.
Received on Tue Nov 18 2008 - 00:36:33 CST