Re: In Oracle, can one calculate statistics on non indexed columns
From: <zigzagdna_at_yahoo.com>
Date: Mon, 25 Jun 2012 04:03:20 -0700 (PDT)
Message-ID: <a576406f-1433-47f6-b505-e899bc7806af_at_googlegroups.com>
On Sunday, June 24, 2012 10:37:57 PM UTC-4, (unknown) wrote:
> 1. I am learning SQL Server 2008. I see that sql server calculates statistics on non indexed columns as well and makes use of such statistics in determining best query plan. I also see something like this in Teradata. Does Oracle do anything like that, if not why not?
> 2. Another thing I noticed that SQL Server calculates string statistics, i.e., for a varcahr column statistics on all substrings in that column. This statistics is useful when where clause uses LIKE:
> name like ‘%Christ%’. Is there anything like in Oracle?
Date: Mon, 25 Jun 2012 04:03:20 -0700 (PDT)
Message-ID: <a576406f-1433-47f6-b505-e899bc7806af_at_googlegroups.com>
On Sunday, June 24, 2012 10:37:57 PM UTC-4, (unknown) wrote:
> 1. I am learning SQL Server 2008. I see that sql server calculates statistics on non indexed columns as well and makes use of such statistics in determining best query plan. I also see something like this in Teradata. Does Oracle do anything like that, if not why not?
> 2. Another thing I noticed that SQL Server calculates string statistics, i.e., for a varcahr column statistics on all substrings in that column. This statistics is useful when where clause uses LIKE:
> name like ‘%Christ%’. Is there anything like in Oracle?
Oracle text indexes are different than normalOracle indexes. One does not really use LIKE instead uses contains.Also syntax for setting text indexes is different from normal index.
Micsrosoft sql server also has text indexes. But string statistics is for normal indexs, as for as I know. Received on Mon Jun 25 2012 - 06:03:20 CDT