--KEY，表示执行时才知道哪个分区
SQL> explain plan for select * from t1 where created>=sysdate-1;
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| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | Pstart| Pstop |
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| 0 | SELECT STATEMENT | | 947 | 163K| 33 (16)| 00:00:01 | | |
| 1 | PARTITION RANGE ITERATOR| | 947 | 163K| 33 (16)| 00:00:01 | KEY | 13 |
|* 2 | TABLE ACCESS FULL | T1 | 947 | 163K| 33 (16)| 00:00:01 | KEY | 13 |
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Predicate Information (identified by operation id):
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2 - filter("CREATED">=SYSDATE@!-1)
SQL> variable x varchar2;
SQL> explain plan for select * from t1 where created>=to_date(:x,'yyyymmdd');
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| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | Pstart| Pstop |
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| 0 | SELECT STATEMENT | | 2099 | 362K| 107 (2)| 00:00:02 | | |
| 1 | PARTITION RANGE ITERATOR| | 2099 | 362K| 107 (2)| 00:00:02 | KEY | 13 |
|* 2 | TABLE ACCESS FULL | T1 | 2099 | 362K| 107 (2)| 00:00:02 | KEY | 13 |
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Predicate Information (identified by operation id):
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2 - filter("CREATED">=TO_DATE(:X,'yyyymmdd'))