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Bug #183

project() isn't considered with index selection.

Added by Andrae Muys - over 11 years ago. Updated over 11 years ago.

Status:
In Progress
Priority:
Normal
Assignee:
Category:
Mulgara
Target version:
-
Start date:
Due date:
% Done:

0%

Estimated time:
Resolution:

Description

select $p from <graph:data> where $s $p $o; uses the GSPO index which requires a full external sort of the store to extract $p. If we use GPOS we get $p without the sort.

The problem is that project() call doesn't participate in index ordering within the query optimisation.

The solution is to introduce an Annotation that allows the project to specify a preferred order. Initially supporting this Annotation with StatementStoreResolution will be sufficient to satisfy the query above. A general solution will also require supporting it with Join and Append tuples.

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