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Check these! [message #232609] Sun, 22 April 2007 04:09 Go to next message
AbbasA
Messages: 2
Registered: April 2007
Junior Member
Hi every body. I have some questions that I didn't find clear answers for them:
1. How can we execute a SELECT statement based on column that has no index?
2. How can we create a secondary index based on a column that has no index?
3. How can we find the size of memory given for each user for sorting?

I hope you can help me!

Regards.
Re: Check these! [message #232611 is a reply to message #232609] Sun, 22 April 2007 05:33 Go to previous messageGo to next message
martijn
Messages: 283
Registered: December 2006
Location: Netherlands
Senior Member
AbbasA wrote on Sun, 22 April 2007 11:09
Hi every body. I have some questions that I didn't find clear answers for them:
1. How can we execute a SELECT statement based on column that has no index?
2. How can we create a secondary index based on a column that has no index?
3. How can we find the size of memory given for each user for sorting?

I hope you can help me!

Regards.


ad 1: Did you try? A column does not have to have a index to be used in a query
ad 2: You can easily look this up on the manuals http://download-uk.oracle.com/docs/cd/B19306_01/server.102/b14200/statements_5010.htm
ad 3: Memory for sorting is in the PGA (Process Global Area), assuming a dedicated server. It's controlled by the parameter sort_area_size. If the process needs more memory then sort_area_size, it will start sorting on disk (very expensive operation).

Maybe someone a bit more knowledgable can tell you some more about (3).
Re: Check these! [message #232614 is a reply to message #232609] Sun, 22 April 2007 07:22 Go to previous messageGo to next message
Michel Cadot
Messages: 64131
Registered: March 2007
Location: Nanterre, France, http://...
Senior Member
Account Moderator
Quote:
I have some questions that I didn't find clear answers for them

Where do you search to not find answers?

Regards
Michel
Re: Check these! [message #232634 is a reply to message #232609] Sun, 22 April 2007 13:33 Go to previous messageGo to next message
AbbasA
Messages: 2
Registered: April 2007
Junior Member
Thanx martijn...

Martin...please don't ask me such "clever" questions!

Re: Check these! [message #232639 is a reply to message #232634] Sun, 22 April 2007 14:30 Go to previous messageGo to next message
martijn
Messages: 283
Registered: December 2006
Location: Netherlands
Senior Member
mmmm I sense some sarcasm/cynism.

I guess you refer to my answer at question 1?

I then probably didn't understood the problem, and assumed you asked a very easy to test-your-self question.

Can you then please elaborate a little more on your first question?
Maybe then I understand it better and give you a more informative answer.
Re: Check these! [message #232641 is a reply to message #232639] Sun, 22 April 2007 15:17 Go to previous messageGo to next message
Littlefoot
Messages: 20897
Registered: June 2005
Location: Croatia, Europe
Senior Member
Account Moderator
I believe OP meant to say "Michel", not "Martin".
Re: Check these! [message #232681 is a reply to message #232641] Mon, 23 April 2007 00:37 Go to previous message
martijn
Messages: 283
Registered: December 2006
Location: Netherlands
Senior Member
mmmmm I think you are rigth...next time I think before I write Smile
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