Comments on: The INSTR Function will Never Use an Index? I will give You a Hint http://hoopercharles.wordpress.com/2010/06/01/the-instr-function-will-never-use-an-index-i-will-give-you-a-hint/ Miscellaneous Random Oracle Topics: Stop, Think, ... Understand Thu, 23 May 2013 04:02:42 +0000 hourly 1 http://wordpress.com/ By: Charles Hooper http://hoopercharles.wordpress.com/2010/06/01/the-instr-function-will-never-use-an-index-i-will-give-you-a-hint/#comment-1334 Wed, 09 Jun 2010 20:53:49 +0000 http://hoopercharles.wordpress.com/?p=2506#comment-1334 Martin,

Thank you for mentioning that it is possible for Oracle to use an INDEX FAST FULL scan for this SQL statement is only the CHAR_COL column is included in the SELECT (I cannot recall if I tried that in my environment, but it certainly is nice that Oracle will use the index). I certainly have learned a lot from test cases like the one in this thread.

]]> By: Martin Preiss http://hoopercharles.wordpress.com/2010/06/01/the-instr-function-will-never-use-an-index-i-will-give-you-a-hint/#comment-1333 Wed, 09 Jun 2010 14:01:07 +0000 http://hoopercharles.wordpress.com/?p=2506#comment-1333 Charles,
I guess the index would also be used, if we use only the column CHAR_COL in the SELECT list. In fact I do not quess but see the INDEX FAST FULL scan, when I use your test case with this adaption (and without a hint).

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