Re: [GENERAL] copy data between database

2005-10-07 Thread Hannes Dorbath
Never used it, but look at contrib/dblink and better use different 
schemas instead of different databases in future -- if you want to 
exchange data.


On 07.10.2005 03:55, [EMAIL PROTECTED] wrote:

Hi, I have a table A in both database d1 and d2. I would like to copy
data in A in d1 to A in d2. How can I do it? I do not want to copy all
data, just some part of A, 


--
Regards,
Hannes Dorbath

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Re: [GENERAL] copy data between database

2005-10-07 Thread Qingqing Zhou

<[EMAIL PROTECTED]> wrote
> Hi, I have a table A in both database d1 and d2. I would like to copy
> data in A in d1 to A in d2. How can I do it? I do not want to copy all
> data, just some part of A,
>
>

Here is a way if you feel want to try. The basic idea is that create a table 
(say OS file name of this table is xxx) for the part of data of A that you 
are interested in d1, and create another table of the same structure in d2 
but empty with OS file name yyy. Then normally shutdown database, replace 
yyy with xxx. Restart database again, you will get the data in d2. Notice 
that you must make sure that two database d1 and d2 are initialized with the 
same parameters.

Regards,
Qingqing 



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Re: [GENERAL] copy data between database

2005-10-10 Thread Scott Marlowe
On Fri, 2005-10-07 at 21:34, Qingqing Zhou wrote:
> <[EMAIL PROTECTED]> wrote
> > Hi, I have a table A in both database d1 and d2. I would like to copy
> > data in A in d1 to A in d2. How can I do it? I do not want to copy all
> > data, just some part of A,
> >
> >
> 
> Here is a way if you feel want to try. The basic idea is that create a table 
> (say OS file name of this table is xxx) for the part of data of A that you 
> are interested in d1, and create another table of the same structure in d2 
> but empty with OS file name yyy. Then normally shutdown database, replace 
> yyy with xxx. Restart database again, you will get the data in d2. Notice 
> that you must make sure that two database d1 and d2 are initialized with the 
> same parameters.

Under no circumstances should you do this with a database that has any
data in it that you value.  pg_dump / pg_restore / psql are the
preferred way of doing this.

Note that for what is being done here, slony would be a great fit as
well, and now that it's available as an rpm, it should be pretty easy to
setup and use.

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Re: [GENERAL] copy data between database

2005-10-10 Thread Qingqing Zhou

"Scott Marlowe" <[EMAIL PROTECTED]> wrote
>
> Under no circumstances should you do this with a database that has any
> data in it that you value.  pg_dump / pg_restore / psql are the
> preferred way of doing this.
>

Oh yeah, sorry for the miss leading information. My method is dangerous and 
can not cover all the cases (say you have an external stored column, etc).

Sorry about it,
Qingqing 



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Re: [GENERAL] copy data between database

2005-10-10 Thread Scott Marlowe
On Mon, 2005-10-10 at 13:53, Qingqing Zhou wrote:
> "Scott Marlowe" <[EMAIL PROTECTED]> wrote
> >
> > Under no circumstances should you do this with a database that has any
> > data in it that you value.  pg_dump / pg_restore / psql are the
> > preferred way of doing this.
> >
> 
> Oh yeah, sorry for the miss leading information. My method is dangerous and 
> can not cover all the cases (say you have an external stored column, etc).
> 
> Sorry about it,
> Qingqing 

No need to apologize.  I do that same kind of thing all the time.  Just
not on production servers is all.  

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