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Stanilovsky Evgeny commented on IGNITE-13030: --------------------------------------------- First part was made in [1] thus i need to edit a little bit this description. [1] https://issues.apache.org/jira/browse/IGNITE-13476 > Calcite integration. Push projections to scans and avoid reading full row > when possible > --------------------------------------------------------------------------------------- > > Key: IGNITE-13030 > URL: https://issues.apache.org/jira/browse/IGNITE-13030 > Project: Ignite > Issue Type: Improvement > Components: sql > Reporter: Roman Kondakov > Priority: Minor > > Currently {{IngiteTableScan}} supports only embedded filters. If it supports > also embedded projections (see {{ProjectableFilterableTable}} in Calcite), it > will be able to push these projections down to page memory scans in order to > avoid full row reading. > For example for the query > {code:java} > SELECT _val FROM tbl > {code} > we can read only values. > Moreover, we can establish index-only scans in some cases. For example, if > the column {{depId}} is indexed, we can the execute query > {code:java} > SELECT depId FROM emp > {code} > using only index tree, without reading rows at all. > -- This message was sent by Atlassian Jira (v8.3.4#803005)