Hi,

I have a query joining on two tables T1 (15.2 million rows) and T2 (285 rows). Please see the explain plan below.

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| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
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| 0 | SELECT STATEMENT | | 1652 | 54516 | 160K (1)| 00:32:06 |
| 1 | HASH GROUP BY | | 1652 | 54516 | 160K (1)| 00:32:06 |
|* 2 | TABLE ACCESS BY INDEX ROWID| T1 | 1652 | 54516 | 160K (1)| 00:32:06 |
|* 3 | INDEX RANGE SCAN | T1_INDX11 | 13M| | 2755 (1)| 00:00:34 |
|* 4 | TABLE ACCESS FULL | T2 | 1 | 25 | 5 (0)| 00:00:01 |
|* 5 | TABLE ACCESS FULL | T2 | 1 | 25 | 5 (0)| 00:00:01 |
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Index range scan on T1 index is taking 34 seconds where as table access by index rowid T1 is taking 32 minutes. T1 is a big table with 250 columns and 15.2 million rows. Is that the reason table access by index rowid taking more time?

Oracle version: 11.02
OS - HPUX

Please let me know if you need any more details to address this.

Thanks,