用merge into进行性能优化(二)
n hash value: 520388833
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| Id | Operation | Name | Rows | Bytes |TempSpc| Cost (%CPU)| Time |
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| 0 | MERGE STATEMENT | | 303K| 5923K| | 4947 (2)| 00:01:00 |
| 1 | MERGE | TEST1 | | | | | |
| 2 | VIEW | | | | | | |
|* 3 | HASH JOIN | | 303K| 53M| 30M| 4947 (2)| 00:01:00 |
| 4 | TABLE ACCESS FULL| TEST2 | 303K| 26M| | 957 (3)| 00:00:12 |
| 5 | TABLE ACCESS FULL| TEST1 | 303K| 26M| | 957 (3)| 00:00:12 |
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Predicate Information (identified by operation id):
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3 - access("T1"."OBJECT_ID"="T2"."OBJECT_ID")
统计信息
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378 recursive calls
310584 db block gets
8547 consistent gets
3751 physical reads
76712320 redo size
678 bytes sent via SQL*Net to client
671 bytes received via SQL*Net from client
4 SQL*Net roundtrips to/from client
1 sorts (memory)
0 sorts (disk)
303258 rows processed
SQL> commit;
提交完成。