db-derby-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From mike matrigali <mikema...@gmail.com>
Subject Re: Blob column behaviour, when we dont have data & when having less data
Date Thu, 04 Dec 2014 18:35:22 GMT
There is no space penalty for any version of derby specifying a larger
blob and/or clob size.  The size is a max size and the only thing derby
does with it is enforce the maximum.   Only space corresponding the
actual data is stored.

See below for inline answers.  they apply to all versions of apache derby.


On 12/4/2014 4:11 AM, kosurusekhar wrote:
> Hi Folks,
> We have requirement to store the files in DB, we created a Blob column. As
> per derby manuals we need to specify the size of the content while creating
> the column. We have 4 different sizes of files like 200KB, 512KB, 1MB, 6MB &
> some times we don't have any content into this column. If I go with max size
> 6MB,
> 1) whether derby will occupy 6MB space for this row even i am not inserting
> data in to this column?
if no data is inserted in this column derby will only store some amount 
of metadata on the order of a few bytes.
> 2) whether derby will occupy complete 6MB space if I am trying to insert
> small size files like 512KB or 1MB?
space used will be that of the size of the inserted column plus some 
metadata overhead/page overhead.
> Please let me know how derby database behaves in this case. I am using Derby
> (Network server) 10.9 version.
> Thanks in Advance.
> Regards
> Sekhar.
> --
> View this message in context: http://apache-database.10148.n7.nabble.com/Blob-column-behaviour-when-we-dont-have-data-when-having-less-data-tp143363.html
> Sent from the Apache Derby Users mailing list archive at Nabble.com.

View raw message