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Index, Please reply ASAP. [message #2850] Fri, 16 August 2002 11:49 Go to next message
JAM
Messages: 3
Registered: August 2002
Junior Member
May be this is not the right place to ask this question.
I am totally not an Oracle person.
I have a question.
For Table XXX (with 200,000 rows) , there is an Index on ColA + Col B.

If there is a select query with
SELECT * FROM TABLE XXX
WHERE ColA = "something"
Does the index ColA+ColB help in fast retrieval than if there was no such index as "ColA + ColB"?

Please direct me to the appropriate forum if this is not the right one.

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Re: Index, Please reply ASAP. [message #2852 is a reply to message #2850] Fri, 16 August 2002 12:45 Go to previous messageGo to next message
Todd Barry
Messages: 4819
Registered: August 2001
Senior Member
Yes, it is very likely that the CBO will use that index for the execution plan. The RBO would certainly use it.

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Re: Index, Please reply ASAP. [message #2858 is a reply to message #2850] Sat, 17 August 2002 07:54 Go to previous message
Abul Fazal
Messages: 39
Registered: February 2002
Member
When u create an index on multiple fields, then the leading column should be used in the where clause. So u'r query will use the Index.

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