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From dmclea...@comcast.net
Subject Re: maximum file size
Date Fri, 10 Nov 2006 16:16:55 GMT
If the OS won't allow a large enough DB file then a local temp file won't work either.

I am  curious about one thing though: Why would it not be a good idea to use multiple tables?
Other than the fact that it would be a practical solution that could actually be implemented
with the current version of Derby that is.

It doesn't seem like it would be very helpful to dismiss a possible solution out of hand without
at least some sort of vague and reasonable explanation.

 -------------- Original message ----------------------
From: "Michael Segel" <msegel@mycingular.blackberry.net>
> Not a good idea to use multiple files.
> Why not go all the way and make derby in to an mpp db? All you would have to do 
> is to preprocess the inbound query then send it off to all of the nodes, taking 
> the result set(s) in to a local temp file and then post process and return the 
> results...  :-)
> -----Original Message-----
> From: dmclean62@comcast.net
> Date: Fri, 10 Nov 2006 14:12:35 
> To:"Derby Discussion" <derby-user@db.apache.org>
> Subject: Re: maximum file size
> You could use multiple tables to get around the file size limit.
> Decide how many rows would go in each table and then use some mechanism for 
> assigning a unique ID to each row. You would then be able to determine which 
> table a specific row is in with an integer division.
> table # = <global row #> / <rows per table>
> local row # = <global row #> % <rows per table>
> The Telemetry Data Warehouse for the Hubble Space Telescope divides the data up 
> by time - each data table contains one calendar year's worth of telemetry data.
> Just a couple of ideas.
>  -------------- Original message ----------------------
> From: Suresh Thalamati <suresh.thalamati@gmail.com>
> > redcloud wrote:
> > > Hi! I need to build a SQL table containing 1000000000 (!!!) rows. But i 
> > > filled up a table with 20000000 rows (file size of table 4GB) and my 
> > > filesystem denied to go on filling up the table. My question is: can 
> > > derby db build "infinitive" size table by chunking in multiple files?
> > 
> > No. Currently a table maps to a single file in Derby. Table size is 
> > limited by the size of the file that can be created on a file system.

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