Re: PK Index V Additional Column INdex

Sybrand Bakker wrote:
>
> On 23 May 2005 07:06:26 -0700, "Thiko!" <biwombi_at_hotmail.com> wrote:
>
> >Hi
> >
> >Having put some SQL through an EXPLAIN PLAN I can see that it is doing
> >an INDEX RANGE SCAN using it's Primary Key index. This if fine.
> >
> >However, I tested creating an index on the column in the WHERE clause
> >and re running the query through the EXPLAIN PLAN. It showed the
> >explain plan to be the same but just using the new index.
> >
> >Would there be an advantage to having the new index created or is using
> >the PK index in the exexution plan fine?
> >
> >This table has around 34000 rows in it.
> >
> >Many thanks for any advice!
> >
> >Thiko!
>
> Remark one: No version
> Remark two: you did gather statistics for this index?
> Whether the index will be used is determined by the cardinality of the
> query expression.
> You could set event 10051 to verify the optimizers decisions.
>
> --
> Sybrand Bakker, Senior Oracle DBA

I think posting about 10053 might be overkill for someone who is asking about whether a new index is good or bad.

hth
connor

-- 
Connor McDonald
Co-author: "Mastering Oracle PL/SQL - Practical Solutions"
Co-author: "Oracle Insight - Tales of the OakTable"

web: http://www.oracledba.co.uk
web: http://www.oaktable.net
email: connor_mcdonald_at_yahoo.com


"Semper in excremento, sole profundum qui variat."

------------------------------------------------------------