Grouper Users - Open Discussion List

[Mark McLaren <>]

On Mon, 27 Dec 2004 09:32:18 -0800, blair christensen 
<>
 wrote:
> On 2004.12.21 11:20, Mark McLaren wrote:
>
> > The next problem I received was "ORA-01450: maximum key length (758)
> > exceeded" error.  To a certain extent this is a database instance
> > specific db_block_size configuration issue. In our case (with a 2K
> > block size) it meant that I had to reduce the length of certain
> > combined constrained columns so that the sum of the lengths would not
> > exceed 758.  Notably these combinations:
> >
> > groupKey, groupField, memberKey, via
> > memberKey, memberID, subjectID, subjectTypeID
> >
> > So I arbitrarily set these lengths for these columns to 100 instead of
> > the 255 that I had initially chosen.
> 
> Ouch.  Should I assume that anyone using a remotely default Oracle
> configuration will run into this problem?

Unfortunately yes.  In Oracle the unique combination of columns that
need to be indexed must fit inside a single db_block for efficient
indexing.  The db_block_size cannot AFAIK be changed with an existing
database instance.
 
> What version of Oracle are you using?  And could I get the database
> schema file you used?  And now it looks like I need to get myself an
> Oracle database to start testing against.

I'll get back to you with these details in due course.

Cheers,

Mark