KC:
In some cases, Oracle can use an index to read the data in sorted order,
thereby eliminating the need for the SORT operation. Check your EXPLAIN
PLANs. If there is a SORT step listed, then Oracle is doing a sort, if not
(and there is a ORDER BY clause on your query) then Oracle is using the
index to read the data in sorted order.
Kevin
-----Original Message-----
Sent: Tuesday, June 05, 2001 10:21 AM
To: Multiple recipients of list ORACLE-L
the order by
Dear list,
Someone ask me when Oracle is doing a sort, will it make a difference if we
use indexed column and non-indexes column in the order by clause, my initial
thinking was index only speed up the retrieval of data from disk, Oracle
probably using other algorithm in sorting records, so indexing is not
relevant in that case. Can someone shed light on this question.
KC
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