Re: Adding Indexes drastically slows down App

From: andrew_webby at hotmail <spam_at_no.thanks.com>
Date: Wed, 20 Jun 2001 16:45:17 +0100
Message-ID: <993051853.8050.0.nnrp-01.c30bdde2@news.demon.co.uk>

Can you do an 'explain plan' for statements with/without the indexes and post them?

"E Elliott" <emelliott_99_at_yahoo.com> wrote in message news:9c4485cf.0106200724.3a57e40e_at_posting.google.com...
> We are seeing drastic slowdowns in our system after adding 2 indexes
> to the largest table in our DB.
>
> Let me give you some background:
> We develop Accounting Software that can use either SQL Server (ugh..I
> know!) or Oracle as its DB backend. As we put out new releases, we
> sometimes need to "Migrate" the database. In our case to migrate
> means to add new columns to a table, add a new table, add new indexes,
> etc.
>
> In our most recent release one of our changes is to add 2 indexes to 2
> separate columns on our biggest table. In a brand new build of the
> new version, everything flies -- even with millions of rows. But,
> when we apply the changes via our migration tools, a 2 minute
> process(generating a report) turns into 45 minutes(the table has 18
> million rows). When we remove the two new indexes, all returns to
<snip> Received on Wed Jun 20 2001 - 10:45:17 CDT