i tried explain plan for select ..
and utlxpls, with asc index are:
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| Operation | Name | Rows | Bytes| Cost | Pstart| Pstop |
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| SELECT STATEMENT | | 1 | 10 | 2 | | |
| SORT AGGREGATE | | 1 | 10 | | | |
| INDEX RANGE SCAN |IDX_FOTOS | 70 | 700 | 2 | | |
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and desc index are;
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| Operation | Name | Rows | Bytes| Cost | Pstart| Pstop |
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| SELECT STATEMENT | | 1 | 10 | 3 | | |
| SORT AGGREGATE | | 1 | 10 | | | |
| TABLE ACCESS BY INDEX RO|FOTOS | 70 | 700 | 3 | | |
| INDEX RANGE SCAN |IDX_FOTOS | 70 | | 2 | | |
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i don´t know interpretate but i think that is better the asc index.Why?¿?, i don´t know.
Thaks.