R help - Apr 2007 - RODBC connections w/o specific database

Folks,

I'm writing a gui wrapper around RODBC (having abandoned RMySQL) and some
custom analysis scripts.  I'm hoping that I could get some advice.

All of my users will have access to a database server.  I am going to limit
their access to certain databases--a sizeable warehouse in a SAN, and then
smaller storage that they can use for temp files and personal tables.  I want to
present these to the user using a tktree widget, rather like you might see in
Enterprise Guide, with the top level of each tree being a specific database and
branches being tables.

Can I get some advice on a good way to accomplish this?

Right now I can create and connect to a DSN that does not specify a database.  I
suppose that upon connection I could use sqlQuery to get the names of databases
and their tables, then use the result to populate the tree.  However, once a
table has been selected, would I need to create a new connection (since the
existing connection does not specify a database) or could I use the existing one
for everything and just specify database and table in my queries?

Also, any additional advice on would be appreciated if anyone has any.

Thanks,

Pete

       
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On Mon, 16 Apr 2007, Pete Cap wrote:
> Folks,
>
> I'm writing a gui wrapper around RODBC (having abandoned RMySQL) and 
> some custom analysis scripts.  I'm hoping that I could get some advice.
>
> All of my users will have access to a database server.  I am going to 
> limit their access to certain databases--a sizeable warehouse in a SAN, 
> and then smaller storage that they can use for temp files and personal 
> tables.  I want to present these to the user using a tktree widget, 
> rather like you might see in Enterprise Guide, with the top level of 
> each tree being a specific database and branches being tables.
>
> Can I get some advice on a good way to accomplish this?
>
> Right now I can create and connect to a DSN that does not specify a 
> database.  I suppose that upon connection I could use sqlQuery to get 
> the names of databases and their tables, then use the result to populate 
> the tree.  However, once a table has been selected, would I need to 
> create a new connection (since the existing connection does not specify 
> a database) or could I use the existing one for everything and just 
> specify database and table in my queries?
You could, but then your tables would all need to accessed via db.table 
names (assuming your DBMS supports that).  Opening a new connection is 
cheap (and will be cheaper in RODBC 1.2.z) so I would just do that.
>
> Also, any additional advice on would be appreciated if anyone has any.
>
> Thanks,
>
> Pete
>
>
> ---------------------------------
>
>
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595

Hello,
If it is not a problem for ODBC, you can use an SQL statemente to change the DB:
"use NAME_OF_DB"
> Folks,
> 
> I'm writing a gui wrapper around RODBC (having abandoned RMySQL) and
some custom analysis scripts.  I'm hoping that I could get some advice.
> 
> All of my users will have access to a database server.  I am going to limit
their access to certain databases--a sizeable warehouse in a SAN, and then
smaller storage that they can use for temp files and personal tables.  I want to
present these to the user using a tktree widget, rather like you might see in
Enterprise Guide, with the top level of each tree being a specific database and
branches being tables.
> 
> Can I get some advice on a good way to accomplish this?
> 
> Right now I can create and connect to a DSN that does not specify a
database.  I suppose that upon connection I could use sqlQuery to get the names
of databases and their tables, then use the result to populate the tree. 
However, once a table has been selected, would I need to create a new connection
(since the existing connection does not specify a database) or could I use the
existing one for everything and just specify database and table in my queries?
> 
> Also, any additional advice on would be appreciated if anyone has any.
> 
> Thanks,
> 
> Pete
> 
>        
> ---------------------------------
> 
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
> 

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http://i-mode.wind.it/

I'm using R in a winXp machine. I have problems with the size of my database
(xyz), anyone know if is possible to use some kind of swap memory, in order
to expand my real RAM and use HD space for the processes?
I'm trying to make a variogram, and I don't want to sacrifice the
precision
of the data, e.g. using mean or median by defined pixels or something like
that (now I have to do that, or use other software like SAS).

Thanks in advance!