下面执行计划的一部分，前者的谓词为非分区key, 后者的谓词为分区key,
反映在执行计划上是由不同，但从他们的上一级HASH JOIN的成本来看，在对全表作PARTITION RANGE
ITERATOR时，有没有走PARTITION KEY对COST影响不大。
-------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost | Pstart| Pstop |
-------------------------------------------------------------------------------------------------------------------
HASH JOIN | | 353 | 22945 | 12803
| 12 | PARTITION RANGE ALL | | | | | 1 | 755 |
|* 13 | TABLE ACCESS FULL | FICT1 | 9145 | 384K| 12763 | 1 | 755 |
------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost | Pstart| Pstop |
------------------------------------------------------------------------------------------------------------------
HASH JOIN | | 353 | 38124 | 12804 | | |
| 11 | PARTITION RANGE ITERATOR | | | | |KEY(MC)|KEY(MC)|
|* 12 | TABLE ACCESS FULL | FICT1 | 9145 | 714K| 12763 |KEY(MC)|KEY(MC)|[@more@]
-------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost | Pstart| Pstop |
-------------------------------------------------------------------------------------------------------------------
HASH JOIN | | 353 | 22945 | 12803
| 12 | PARTITION RANGE ALL | | | | | 1 | 755 |
|* 13 | TABLE ACCESS FULL | FICT1 | 9145 | 384K| 12763 | 1 | 755 |
------------------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost | Pstart| Pstop |
------------------------------------------------------------------------------------------------------------------
HASH JOIN | | 353 | 38124 | 12804 | | |
| 11 | PARTITION RANGE ITERATOR | | | | |KEY(MC)|KEY(MC)|
|* 12 | TABLE ACCESS FULL | FICT1 | 9145 | 714K| 12763 |KEY(MC)|KEY(MC)|[@more@]
来自 “ ITPUB博客 ” ，链接：https://blog.itpub.net/661919/viewspace-1030001/ ，如需转载，请注明出处，否则将追究法律责任。
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