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Christian Beikov commented on CALCITE-1965: ------------------------------------------- The paper is a bit hard to follow for me, the first one(from Goldstein) was a lot less formal and easier to read. I guess I understand some of the basic concepts, but I am unsure if it's that easy to implement. Maybe you([~jcamachorodriguez]) understand it better and have an idea of how to implement it? I could try to give it a shot next week or so, but I'd first like to hear your opinion on the paper and the approach. > Support outer joins for materialized views > ------------------------------------------ > > Key: CALCITE-1965 > URL: https://issues.apache.org/jira/browse/CALCITE-1965 > Project: Calcite > Issue Type: Improvement > Components: core > Reporter: Christian Beikov > Assignee: Julian Hyde > > Currently, only inner joins are supported for materialized view > substitutions. The support for outer joins involves creating new pulled up > predicates in case of outer joins that represent semantics of the join. For a > join predicate like "a.id = b.id" the inner join just pulls up that > predicate. When having a left join like e.g. {{select * from a left join b on > a.id = b.id}}, the actual pulled up predicate would be {{OR(=(a.id, > b.id),ISNULL(b.id))}}. For a right join it would be {{OR(=(a.id, > b.id),ISNULL(a.id))}} and for a full outer join it would be {{OR(=(a.id, > b.id),ISNULL(a.id),ISNULL(b.id))}} -- This message was sent by Atlassian JIRA (v6.4.14#64029)