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From:Rhino Date:December 23 2004 5:12pm
Subject:Re: Tables "shortcuts"?
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If MySQL works like DB2 - in most respects, they behave the same - a view
based on a Join is ALWAYS read-only.

Rhino

----- Original Message ----- 
From: <SGreen@stripped>
To: "Rhino" <rhino1@stripped>
Cc: "mysql" <mysql@stripped>; "Nico Alberti" <nico.alberti@stripped>
Sent: Thursday, December 23, 2004 11:54 AM
Subject: Re: Tables "shortcuts"?


> Yes, it should be possible to 'alias' an entire table through a view
> (assuming your version of MySQL has views). Views will be "updateable" so
> long as none of the columns are computed. That means that a view based on
> SELECT * FROM tablename should give you two options
>         a) you can call your VIEWs columns anything you want (so you can
> match your legacy table's old names)
>         b) it will be updateable. You can read from and write to the view
> just as you would have the original table.
>
> HOWEVER!!
> The view will still have to obey any constraints placed on the source
> table.
> You will only be able to insert and update columns presented in the view.
> Base table columns not presented in the view will be "invisible".
> I have no idea if a query using two or more tables can act as the base
> definition of an updateable view.
>
> Another option could be to look at what the developers are calling
> "federated" databases. That works like a "linked table" (to use an M$
> term) in that you have a table name in your database (local reference) but
> the data actually resides on a different server. Both are coming soon to
> production-ready MySQL. Right now both features are in the testing and
> development phases.
>
> My advice is to check out the new 5.x+ and test it to discover what works
> and what doesn't for what you would like it to do. Perhaps it is stable
> enough to meet your needs but I leave that determination up to you.
>
> Shawn Green
> Database Administrator
> Unimin Corporation - Spruce Pine
>
>
> "Rhino" <rhino1@stripped> wrote on 12/23/2004 11:30:34 AM:
>
> >
> > ----- Original Message ----- 
> > From: "Nico Alberti" <nico.alberti@stripped>
> > To: "Rhino" <rhino1@stripped>
> > Sent: Thursday, December 23, 2004 10:25 AM
> > Subject: Re: Tables "shortcuts"?
> >
> >
> > > On Thu, 23 Dec 2004 08:46:13 -0500, Rhino <rhino1@stripped>
> wrote:
> > > >
> > >
> > > > I am not very clear on what you want to do. Your English is fine but
> you
> > > > haven't explained the problem and what you want to do in sufficient
> > detail.
> > > >
> > >
> > > Thank you Rhino for your answer.
> > >
> > > I would like to do a thing like this:
> > >
> > > A table, say: olddb.table1 is moved to newdb.table1. Every application
> > > (let's forget about Access now) has to change its query accordingly.
> > >
> > > What I was asking is if there is some trick that can make appear a
> > > "bogus" table1 in olddb that references to the new position of table1,
> > > so any query can work as before  affecting the "real" table1 in newdb.
> > >
> > > For what I know this could be a job that can be done by a view (even
> > > if, using 4.1 I can not use them).
> > >
> > > Of course this is not a blocking problem, I was only wondering if
> > > there was a way to save me some work :-)
> > >
> > Nico,
> >
> > It is always best if you post followup questions/remarks back to the
> list.
> > This makes it possible for everyone on the list to follow the
> conversation
> > and to help you. It also ensures that the conversation will be stored on
> the
> > MySQL archive so that others can learn from it in the future. That is
> why I
> > am sending this reply to the list, not just to you directly.
> >
> > I don't know of a way to do what you want to do in MySQL. I am
> relatively
> > new to MySQL myself. I just looked in the manual and didn't see anything
> > that does what you want to do but maybe I just didn't look in the right
> > place. It sounds like you are describing something like a Unix symbolic
> link
> > but I don't know of any way to do that within MySQL.
> >
> > Maybe someone else on the list has an idea that can help you.
> >
> > Rhino
> >
> >
> > -- 
> > MySQL General Mailing List
> > For list archives: http://lists.mysql.com/mysql
> > To unsubscribe:    http://lists.mysql.com/mysql?unsub=1
> >
>

Thread
Tables "shortcuts"?Nico Alberti23 Dec
  • Re: Tables "shortcuts"?Rhino23 Dec
    • Re: Tables "shortcuts"?SGreen23 Dec
      • Re: Tables "shortcuts"?Rhino23 Dec
        • Re: Tables "shortcuts"?SGreen23 Dec
      • Re: Tables "shortcuts"?Nico Alberti23 Dec
    • Re: Tables "shortcuts"?Nico Alberti23 Dec