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Can I use Oracle Hint to use index in a query which uses UNION [message #501745] Thu, 31 March 2011 01:13 Go to next message
arijitdey80
Messages: 1
Registered: March 2011
Location: IN
Junior Member
I have a SQL query where I am making UNION of two select statements. The table that I am joining in each select statement have indexes defined for those tables.

Now the UNION of the two select statements again in enclosed in an inline view , from which I fetching my final field values.

The select statements inside the inline view returns huge number of row (like 50 million rows).

The whole query fails with time out.

How can I optimize this query further?

Is there a way to pass Oracle Hints so that Oracle uses indexes?

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Re: Can I use Oracle Hint to use index in a query which uses UNION [message #501749 is a reply to message #501745] Thu, 31 March 2011 01:52 Go to previous message
Michel Cadot
Messages: 54672
Registered: March 2007
Location: Nanterre, France, http://...
Senior Member
Account Moderator
Read http://www.orafaq.com/forum/mv/msg/84315/433888/102589/#msg_433888 and post the required information.

Regards
Michel

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