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

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

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

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  -- Matthew Buckett, VLE Developer
  -- Learning Technologies Group, Oxford University Computing Services
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