Обсуждение: Schema overlay question

Hi All,

A simple question to the list.
We are designing a database, the database has three major components (each component with 4-8 tables)
two components are ready, is it possible to 'overlay' the third one later? or
Do i have to drop all the components (along with data!!!) and then add the third component and then build the entire DB?
What i am saying is some tables are existing, could i later add a bunch of tables at a later date without dropping the entire database?
Thanks for your help.

Regards,
Hrisih

Hrishikesh Deshmukh <hdeshmuk@gmail.com> writes:

> What i am saying is some tables are existing, could i later add a bunch of
> tables at a later date without dropping the entire database?

Sure, you can do CREATE TABLE at any time.

-Doug

On Fri, Sep 02, 2005 at 05:28:11PM -0400, Hrishikesh Deshmukh wrote:
> We are designing a database, the database has three major components (each
> component with 4-8 tables)
> two components are ready, is it possible to 'overlay' the third one later?
> or
> Do i have to drop all the components (along with data!!!) and then add the
> third component and then build the entire DB?
> What i am saying is some tables are existing, could i later add a bunch of
> tables at a later date without dropping the entire database?

What exactly do you mean by "overlay"?  As far as the database is
concerned, you can create tables any time you want: today, tomorrow,
or a year from now.  Is there some specific case you're concerned
about?  If so then please elaborate.

--
Michael Fuhr

HI All,

What i meant was when the third component of tables are ready and i can create tables any time what happens to relationships when i am building the third component tables? How smooth the process will be?

Regards,
Hrishi

On Fri, Sep 02, 2005 at 07:16:04PM -0400, Hrishikesh Deshmukh wrote:
> What i meant was when the third component of tables are ready and i can
> create tables any time what happens to relationships when i am building the
> third component tables? How smooth the process will be?

What relationships?  How do you anticipate the "third component"
tables possibly interfering with tables that have already been
created?  It's still not clear what you're concerned about, since
one can certainly create and use one set of tables, then at some
later time create and use another set of tables.  Apparently there's
something about creating that later set of tables that concerns
you, but we don't know what that concern is based on.

--
Michael Fuhr