List:General Discussion« Previous MessageNext Message »
From:Johnny Withers Date:May 11 2009 9:09pm
Subject:Re: Merging Databases
View as plain text  
We don't want to use a view because then this database will not
be consistent with the others.
We can't simply use a select from .. insert into because when we renumber
table1's ID column, items in table2 and 3 and so on may link to the ID
column in that table. So we need to update the ID column in table1, then add
the same # to the table1_id columns in any other table. After we do this, we
could do the select from.. insert into method I suppose.

-jw

On Mon, May 11, 2009 at 2:49 PM, Weston, Craig (OFT) <
Craig.Weston@stripped> wrote:

>
>
> -----Original Message-----
> From: Johnny Withers [mailto:johnny@stripped]
> Sent: Monday, May 11, 2009 3:30 PM
> To: MySQL General List
> Subject: Merging Databases
>
> Hi,
> I have a lot of databases that have the exact same tables and each table
> has
> the exact same column structure. I'm looking at merging two of these
> databases together into a single database (Company A bought Company B and
> wants the data from A combined into B now).
>
> I've been tossing around the idea of looking in database B at each table
> that would need to be "merged" and simply adding the last ID number to
> every
> ID number in database A's tables. For example, in table1 in B's data, the
> last ID number is 2000, could we simply add 2000 to every ID number in
> table1 in A's data? Could we then export (SELECT INTO OUTFILE) from A's
> data
> and import (LOAD DATA) into B's data?
>
> Has anyone done something like this before? Did you have problems?
>
> --
> -----------------------------
> Johnny Withers
> 601.209.4985
> johnny@stripped
>
> ---
>
> Why not create a view and just concatenate on an identifier? This way the
> data can be kept in the same forms.
>
> Or, if you do want to have it as one table, you can use a select insert
> statement to move from one to another. Build the select query first to get
> the data looking like you want it, then convert it when you think you are
> ready.
>
> Of course, backups are your friend in any case.  :)
>
>
> Cheers,
> Craig
>
>
> This e-mail, including any attachments, may be confidential, privileged or
> otherwise legally protected. It is intended only for the addressee. If you
> received this e-mail in error or from someone who was not authorized to send
> it to you, do not disseminate, copy or otherwise use this e-mail or its
> attachments.  Please notify the sender immediately by reply e-mail and
> delete the e-mail from your system.
>
>
> --
> MySQL General Mailing List
> For list archives: http://lists.mysql.com/mysql
> To unsubscribe:    http://lists.mysql.com/mysql?unsub=1
>
>


-- 
-----------------------------
Johnny Withers
601.209.4985
johnny@stripped

Thread
Merging DatabasesJohnny Withers11 May
  • RE: Merging DatabasesOFT)11 May
    • Re: Merging DatabasesJohnny Withers11 May
      • Re: Merging DatabasesChris Clarke11 May
      • RE: Merging DatabasesAndrew Braithwaite11 May