| hint: first_rows [message #277041] |
Sun, 28 October 2007 03:20  |
tanmoy1048
Messages: 133
Registered: June 2007
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I m working with oracle 10.2.0.2 in solaris
I am trying to use first_row hint. but it is not working. it has a ORDER_BY clause but that column has index.
No distinct is there.
so what kind of problem is there?I checked the execution plan..both r same.
[Updated on: Sun, 28 October 2007 03:22] Report message to a moderator |
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| Re: hint: first_rows [message #277051 is a reply to message #277041] |
Sun, 28 October 2007 04:12  |
tanmoy1048
Messages: 133
Registered: June 2007
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Senior Member |
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>Why are you trying a hint?
bcos I work with OLTP system.
>What does "is not working" mean?
with the hint and without the hint....same execution plan is given.
>What is your Oracle version?
I have given in my starting post.
>What is the relation between index and order by clause?
so far I kno..The optimizer ignores this hint in SELECT statement blocks that contain ORDER BY clauses, when there is no index on the ordering columns.
>Why do you think this would change the execution plan?
coz I m trying to change the plan as it has lots of hash join.
>What is the execution plan?
that I got after executing the sql by autotrace on.
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| Re: hint: first_rows [message #277060 is a reply to message #277041] |
Sun, 28 October 2007 05:34 |
tanmoy1048
Messages: 133
Registered: June 2007
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Senior Member |
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I dont need all the rows at a time.So I need to use this hint.And I actually didnt told which one is better.I just asked why the plan is same.
So..order by doesnt related to hint using????
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| Re: hint: first_rows [message #277063 is a reply to message #277060] |
Sun, 28 October 2007 06:00 |
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vamsi kasina
Messages: 2112
Registered: October 2003
Location: Cincinnati, OH
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Senior Member |
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| Quote: |
>What is the execution plan?
that I got after executing the sql by autotrace on.
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It meant to post your execution plan here. Michel is not asking, how did you get the execution plan?
Also post your sql statement.
By
Vamsi
[Updated on: Sun, 28 October 2007 06:02] Report message to a moderator |
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| Re: hint: first_rows [message #277070 is a reply to message #277067] |
Sun, 28 October 2007 06:49 |
tanmoy1048
Messages: 133
Registered: June 2007
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Senior Member |
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| Michel Cadot wrote on Sun, 28 October 2007 06:24 |
Maybe, maybe not, OP does not want to explain, he does not want to post his plan, he does not want many things but he want our help without giving any clue.
Regards
Michel
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what clues do u need,michel ?? and how can I post the plan...it will exceed the limit of characters.And thanks vamsi kasina, u got the point.
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