Re: [Bodington-developers] Wtd: Expertise on uploaded_files table structure

[Matthew B. <mat...@ou...>]

Matthew Buckett wrote:
> Matthew Buckett wrote:
> 
>>Peter Crowther wrote:
>>
>>
>>>>From: Matthew Buckett
>>>>Nulls don't end up in the index on PostgreSQL
>>>
>>>
>>>Ah.  Oh.  Oh dear.
>>>
>>>
>>>>Sounds like this is a PostgreSQL/MSSQL/HSQLDB difference.
>>>
>>>
>>>It is.  Not sure whether / which way ANSI mandates this, but (as we've
>>>seen) the behaviour cannot be relied upon.
>>
>>
>>And MSSQL doesn't support partial indexes either?
>>
>>CREATE UNIQUE INDEX uploaded_files_unq_name ON uploaded_files
>>(parent_uploaded_file_id, name) WHERE parent_uploaded_file_id IS NOT NULL
> 
> 
> Ok I pulled out the indexes unless someone has a better solution for MSSQL.
> 

The only solutions I can find all seem to invlove allot of mess
(triggers, views, computed constraints).

http://www.sql-server-performance.com/q&a133.asp

-- 
 -- Matthew Buckett, VLE Developer
 -- Learning Technologies Group, Oxford University Computing Services
 -- Tel: +44 (0)1865 283660 http://www.oucs.ox.ac.uk/ltg/