Re: Column order in indices (oracle 9.2)

Goran,

In my case I don't have any range conditions. My query is select * from table where column='zzz';

thank you

Gene Gurevich

                                                                           
             "goran                                                        
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             08/01/2006 08:03          sac_at_uillinois.edu, oracle-l         
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                                       Re: Column order in indices (oracle 
                                       9.2)                                
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           

Pay also attention if some of those columns has been used in the where clause with a range condition.
If such, put this column(s) at the end of the index. The reason why, you can find in the book of J.Lewis.
CBO walk the mysterious ways :-)

On 8/1/06, Schultz, Charles <sac_at_uillinois.edu> wrote:   The column order does matter, but Oracle can SKIP SCAN an index in the   situation you talk about. To determine exactly what is going on, you   should at least get an explain plan of your sql. I imagine there are   other factors involved.

-----Original Message-----

  From: oracle-l-bounce_at_freelists.org
  [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of   genegurevich_at_discoverfinancial.com
  Sent: Tuesday, August 01, 2006 7:44 AM   To: oracle-l
  Subject: Column order in indices (oracle 9.2)

  Hi everybody:

  I remember reading that in Oracle 9.2 and higher the order of the   columns in an index does not matter.
  That is oracle will be able to quickly search on a column even if it is   not a leading one. I have a table with a primary key consisting of three   columns. When a table is queried based on the third column, the data   start coming out immediately, but when I use the second column the query   just sits there.
  Is that an expected behavior? Did I misunderstood something about the   column order?

  thanks for any insight

  Gene Gurevich

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