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Use index to avoid full table scan

Use index to avoid full table scan

(OP)
Oracle 11.2 G

I am joining a table where I only need two fields the join key and one other field. If I created a concatenated index that contained the two fields would oracle determine that it can get all the needed information from the index and avoid a full table scan. The table has 71 million rows with an avg length of 307 bytes and takes 500K blocks. So, I would like to avoid the I/O necessary to read this table.

Thank you.

RE: Use index to avoid full table scan


Go for it! thumbsup2

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The person who says it can't be done should not interrupt the person doing it. -- Chinese proverb

RE: Use index to avoid full table scan

Oracle may utilize its INDEX FAST FULL SCAN method and read all fields directly from index not accessing table at all. But only in case your query uses only those 2 fields in index.

Regards, Dima
http://seminihin.narod.ru

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