并行与hint同时存在
Posted dayu-liu
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1.指定并行度为3
select /*+ parallel(t1,3) */ object_type,count(*) from PARALLEL_TEST1 t1 group by object_type order by count(*);
select /*+ parallel(t1,3) */ object_type,count(*) from PARALLEL_TEST1 t1 group by object_type order by count(*);SQL>
OBJECT_TYPE COUNT(*)
--------------------------------------------------------------------- ----------
EDITION 1
RULE 2
DESTINATION 2
JAVA SOURCE 2
SCHEDULE 4
SCHEDULER GROUP 4
LOB PARTITION 7
DIRECTORY 7
INDEXTYPE 7
UNIFIED AUDIT POLICY 8
WINDOW 9
CLUSTER 10
CONTEXT 10
PROGRAM 10
RESOURCE PLAN 11
EVALUATION CONTEXT 12
JOB CLASS 14
UNDEFINED 15
CONSUMER GROUP 18
RULE SET 18
JOB 23
QUEUE 25
TABLE SUBPARTITION 32
XML SCHEMA 44
OPERATOR 54
INDEX PARTITION 187
PROCEDURE 201
LIBRARY 228
TYPE BODY 229
SEQUENCE 254
TABLE PARTITION 258
JAVA DATA 309
FUNCTION 346
TRIGGER 593
LOB 857
JAVA RESOURCE 1015
PACKAGE BODY 1245
PACKAGE 1306
TABLE 2388
TYPE 2536
INDEX 4268
VIEW 6487
JAVA CLASS 30816
SYNONYM 37081
44 rows selected.
Execution Plan
----------------------------------------------------------
Plan hash value: 4204599738
---------------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | TQ |IN-OUT| PQ Distrib |
---------------------------------------------------------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 82500 | 1047K| 159 (4)| 00:00:01 | | | |
| 1 | PX COORDINATOR | | | | | | | | |
| 2 | PX SEND QC (ORDER) | :TQ10002 | 82500 | 1047K| 159 (4)| 00:00:01 | Q1,02 | P->S | QC (ORDER) |
| 3 | SORT ORDER BY | | 82500 | 1047K| 159 (4)| 00:00:01 | Q1,02 | PCWP | |
| 4 | PX RECEIVE | | 82500 | 1047K| 159 (4)| 00:00:01 | Q1,02 | PCWP | |
| 5 | PX SEND RANGE | :TQ10001 | 82500 | 1047K| 159 (4)| 00:00:01 | Q1,01 | P->P | RANGE |
| 6 | HASH GROUP BY | | 82500 | 1047K| 159 (4)| 00:00:01 | Q1,01 | PCWP | |
| 7 | PX RECEIVE | | 82500 | 1047K| 159 (4)| 00:00:01 | Q1,01 | PCWP | |
| 8 | PX SEND HASH | :TQ10000 | 82500 | 1047K| 159 (4)| 00:00:01 | Q1,00 | P->P | HASH |
| 9 | HASH GROUP BY | | 82500 | 1047K| 159 (4)| 00:00:01 | Q1,00 | PCWP | |
| 10 | PX BLOCK ITERATOR | | 82500 | 1047K| 155 (1)| 00:00:01 | Q1,00 | PCWC | |
| 11 | TABLE ACCESS FULL| PARALLEL_TEST1 | 82500 | 1047K| 155 (1)| 00:00:01 | Q1,00 | PCWP | |
---------------------------------------------------------------------------------------------------------------------------
Note
-----
- dynamic statistics used: dynamic sampling (level=2)
- Degree of Parallelism is 3 because of table property
Statistics
----------------------------------------------------------
26 recursive calls
0 db block gets
1941 consistent gets
107 physical reads
0 redo size
1834 bytes sent via SQL*Net to client
573 bytes received via SQL*Net from client
4 SQL*Net roundtrips to/from client
4 sorts (memory)
0 sorts (disk)
44 rows processed
DBMS_SQLTUNE.REPORT_SQL_MONITOR(SESSION_ID=>40)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
SQL Monitoring Report
SQL Text
------------------------------
select /*+ parallel(t1,3) */ object_type,count(*) from PARALLEL_TEST1 t1 group by object_type order by count(*)
Global Information
------------------------------
Status : DONE (ALL ROWS)
Instance ID : 1
Session : SYS (40:34283)
SQL ID : 84vj8sv8vuxja
SQL Execution ID : 16777216
Execution Started : 08/24/2018 11:09:37
First Refresh Time : 08/24/2018 11:09:37
Last Refresh Time : 08/24/2018 11:09:37
Duration : .024032s
Module/Action : [email protected] (TNS V1-V3)/-
Service : dayupdb1
Program : [email protected] (TNS V1-V3)
Fetch Calls : 4
Global Stats
======================================================================================
| Elapsed | Cpu | IO | Cluster | Other | Fetch | Buffer | Read | Read |
| Time(s) | Time(s) | Waits(s) | Waits(s) | Waits(s) | Calls | Gets | Reqs | Bytes |
======================================================================================
| 0.09 | 0.06 | 0.01 | 0.01 | 0.02 | 4 | 1813 | 13 | 856KB |
======================================================================================
Parallel Execution Details (DOP=3 , Servers Allocated=6)
Instances : 2
==========================================================================================================================================
| Instance | Name | Type | Server# | Elapsed | Cpu | IO | Cluster | Other | Buffer | Read | Read | Wait Events |
| | | | | Time(s) | Time(s) | Waits(s) | Waits(s) | Waits(s) | Gets | Reqs | Bytes | (sample #) |
==========================================================================================================================================
| 1 | PX Coordinator | QC | | 0.02 | 0.01 | | | 0.01 | 5 | | . | |
| 1 | p000 | Set 1 | 1 | 0.02 | 0.01 | 0.00 | 0.00 | 0.00 | 752 | 3 | 128KB | |
| 1 | p001 | Set 1 | 2 | 0.02 | 0.01 | 0.00 | 0.00 | 0.01 | 658 | 3 | 112KB | |
| 2 | p000 | Set 1 | 3 | 0.02 | 0.01 | 0.01 | 0.00 | | 398 | 7 | 616KB | |
| 1 | p002 | Set 2 | 1 | 0.00 | 0.00 | | | | | | . | |
| 1 | p003 | Set 2 | 2 | 0.00 | 0.00 | | | 0.00 | | | . | |
| 2 | p001 | Set 2 | 3 | 0.00 | 0.00 | | | | | | . | |
==========================================================================================================================================
Instance Drill-Down
================================================================================================================================
| Instance | Process Names | Elapsed | Cpu | IO | Cluster | Other | Buffer | Read | Read | Wait Events |
| | | Time(s) | Time(s) | Waits(s) | Waits(s) | Waits(s) | Gets | Reqs | Bytes | |
================================================================================================================================
| 1 | QC p000 p001 p002 p003 | 0.07 | 0.04 | 0.01 | 0.00 | 0.02 | 1415 | 6 | 240KB | |
| 2 | p000 p001 | 0.02 | 0.02 | 0.01 | 0.00 | | 398 | 7 | 616KB | |
================================================================================================================================
SQL Plan Monitoring Details (Plan Hash Value=4204599738)
====================================================================================================================================================================
| Id | Operation | Name | Rows | Cost | Time | Start | Execs | Rows | Read | Read | Mem | Activity | Activity Detail |
| | | | (Estim) | | Active(s) | Active | | (Actual) | Reqs | Bytes | (Max) | (%) | (# samples) |
====================================================================================================================================================================
| 0 | SELECT STATEMENT | | | | 1 | +0 | 7 | 44 | | | | | |
| 1 | PX COORDINATOR | | | | 1 | +0 | 7 | 44 | | | | | |
| 2 | PX SEND QC (ORDER) | :TQ10002 | 82500 | 159 | 1 | +0 | 3 | 44 | | | | | |
| 3 | SORT ORDER BY | | 82500 | 159 | 1 | +0 | 3 | 44 | | | 6144 | | |
| 4 | PX RECEIVE | | 82500 | 159 | 1 | +0 | 3 | 44 | | | | | |
| 5 | PX SEND RANGE | :TQ10001 | 82500 | 159 | 1 | +0 | 3 | 44 | | | | | |
| 6 | HASH GROUP BY | | 82500 | 159 | 1 | +0 | 3 | 44 | | | 5M | | |
| 7 | PX RECEIVE | | 82500 | 159 | 1 | +0 | 3 | 105 | | | | | |
| 8 | PX SEND HASH | :TQ10000 | 82500 | 159 | 1 | +0 | 3 | 105 | | | | | |
| 9 | HASH GROUP BY | | 82500 | 159 | 1 | +0 | 3 | 105 | | | 6M | | |
| 10 | PX BLOCK ITERATOR | | 82500 | 155 | 1 | +0 | 3 | 90953 | | | | | |
| 11 | TABLE ACCESS FULL | PARALLEL_TEST1 | 82500 | 155 | 1 | +0 | 39 | 90953 | 13 | 856KB | | | |
====================================================================================================================================================================
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