Re: Is there a way to add a new column to a table while the table is being used for queries???
From: ddf <oratune_at_msn.com>
Date: Thu, 12 Jan 2012 12:22:44 -0800 (PST)
Message-ID: <1a65331e-68be-4066-96ab-99cc225e1445_at_y12g2000yqc.googlegroups.com>
On Jan 12, 1:01 pm, jack_go..._at_yahoo.com wrote:
> I require the ability to add a new clob field to a database table
> object on Oracle 10g SQL server.
> Can I just do an
> alter table MyTable add column mynewfield clob;
>
> How do I insure that users can continue to make queries on the
> table???
>
> I would be greatful if someone could point me to some documentation on
> this subject of high availability in a huge partitioned data warehouse
> type environment.
>
> Thank you in advance!
Date: Thu, 12 Jan 2012 12:22:44 -0800 (PST)
Message-ID: <1a65331e-68be-4066-96ab-99cc225e1445_at_y12g2000yqc.googlegroups.com>
On Jan 12, 1:01 pm, jack_go..._at_yahoo.com wrote:
> I require the ability to add a new clob field to a database table
> object on Oracle 10g SQL server.
> Can I just do an
> alter table MyTable add column mynewfield clob;
>
> How do I insure that users can continue to make queries on the
> table???
>
> I would be greatful if someone could point me to some documentation on
> this subject of high availability in a huge partitioned data warehouse
> type environment.
>
> Thank you in advance!
The users can continue to query the table but have you really given thought as to what you might break by adding this column 'on the fly'? You mention this is a DW environment which can contain materialized views, some of which may be defined by the dreaded 'select *' queries. Adding a column to a table without first checking what other objects reference that table (MVs, procedures, functions, packages, views) could cause problems later; it's not just the ad-hoc queries you need to concern yourself with.
David Fitzjarrell Received on Thu Jan 12 2012 - 14:22:44 CST