SQL> SELECT COUNT(*) FROM sales_range
  2  WHERE TO_CHAR(sales_date,'YYYYMM')='200605';

  COUNT(*)
----------
     44641
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| Id  | Operation            | Name        | Rows  | Bytes | Cost (%CPU)| Time     | PstartPstop |
----------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT     |             |     1 |     8 |   877  (38)| 00:00:11 |       |       |
|   1 |  SORT AGGREGATE      |             |     1 |     8 |            |          |       |       |
|   2 |   PARTITION RANGE ALL|             |  5267 | 42136 |   877  (38)| 00:00:11 |     1 |     4 |
|*  3 |    TABLE ACCESS FULL | SALES_RANGE |  5267 | 42136 |   877  (38)| 00:00:11 |     1 |     4 |
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リスト4 パーティション・キーを条件にしても機能しない例