PLAN_TABLE_OUTPUT
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Plan hash value: 2822030489
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| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
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PLAN_TABLE_OUTPUT
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| 0 | SELECT STATEMENT | | 1 | 46 | 2 (0)| 00:00:01 |
| 1 | TABLE ACCESS BY INDEX ROWID| PURCHASE | 1 | 46 | 2 (0)| 00:00:01 |
|* 2 | INDEX UNIQUE SCAN | PK_PURCHASENO | 1 | | 1 (0)| 00:00:01 |
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PLAN_TABLE_OUTPUT
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Predicate Information (identified by operation id):
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2 - access("PURCHASENO"=9989)
14 rows selected.
有人可以向我解釋這是什麼意思?Oracle優化器執行查詢
這是否意味着Oracle正在使用索引來執行此查詢?
'PURCHASENO'是一個主鍵,它有一個唯一索引,所以是的 - oracle選擇一個索引訪問路徑。 – haki
「INDEX UNIQUE SCAN」不是一個線索嗎?你看過[性能調整指南](http://docs.oracle.com/cd/E29597_01/server.1111/e16638/optimops.htm#i82029)嗎? –
@AlexPoole是的,我只是想確保爲了完全回答這個問題。 – Jim