calcite-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Milinda Pathirage <mpath...@umail.iu.edu>
Subject Merging Project and Scan when there are RexCalls in projections
Date Wed, 18 Mar 2015 14:51:18 GMT
Hi Julian,

I am trying to understand why Project and Scan merging is avoided when
there are projections which are RexCalls. Is this a purely implementation
related rule (such as separation of concerns or keeping scan as simple as
possible) or is there any theoretical background for this.

I am asking this because I discovered that Project#getMapping returns null
when there are RexCalls in the projection which prevent ProjectableScanRule
from transforming the logical expression tree.

Thanks in advance,
Milinda

-- 
Milinda Pathirage

PhD Student | Research Assistant
School of Informatics and Computing | Data to Insight Center
Indiana University

twitter: milindalakmal
skype: milinda.pathirage
blog: http://milinda.pathirage.org

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message