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explain plan for select *  from p800 where owner='SCOTT';

select * from table(dbms_xplan.display());


PLAN_TABLE_OUTPUT
Plan hash value: 983731221
 
-----------------------------------------------------------------------------------------
| Id  | Operation                   | Name      | Rows  | Bytes | Cost (%CPU)| Time     |
-----------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT            |           |   874 |   176K|    38   (0)| 00:00:01 |
|   1 |  TABLE ACCESS BY INDEX ROWID| P800      |   874 |   176K|    38   (0)| 00:00:01 |
|*  2 |   INDEX RANGE SCAN          | P800_IDX2 |   874 |       |     5   (0)| 00:00:01 |
-----------------------------------------------------------------------------------------
 
Predicate Information (identified by operation id):
---------------------------------------------------
 
   2 - access("OWNER"='SCOTT')
 
Note
-----
   - dynamic sampling used for this statement (level=2)




SESSION_ID	1141	
SQL_ID	9tfy5uz2vshqn	
MACHINE	WORKGROUPTLCB-PC	
BLOCKING_SESSION		
SAMPLE_TIME	10-4月 -19 08.36.59.183 下午	
MODULE	PL/SQL Developer	
PROGRAM	plsqldev.exe	
EVENT	db file sequential read	
P1	4	
P1TEXT	file#	
P2	88356	
P2TEXT	block#	
P3	1	
P3TEXT	blocks	
SQL_TEXT	select *  from p800 where owner='SCOTT' 	



select owner,segment_name,segment_type,partition_name from dba_extents where file_id=4 and 88356 between block_id and block_id+blocks-1;

SQL> select owner,segment_name,segment_type,partition_name from dba_extents where file_id=4 and 88356 between block_id and block_id+blocks-1;

OWNER	   SEGMENT_NAME 		  SEGMENT_TYPE			 PARTITION_NAME
---------- ------------------------------ ------------------------------ ------------------------------------------------------------------------------------------
TEST	   P800 			  TABLE