[ https://issues.apache.org/jira/browse/HAWQ-1404?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Oleksandr Diachenko reassigned HAWQ-1404: ----------------------------------------- Assignee: Oleksandr Diachenko (was: Ed Espino) > PXF to leverage file-level stats of ORC file and emit records for COUNT(*) > -------------------------------------------------------------------------- > > Key: HAWQ-1404 > URL: https://issues.apache.org/jira/browse/HAWQ-1404 > Project: Apache HAWQ > Issue Type: Improvement > Components: PXF > Reporter: Oleksandr Diachenko > Assignee: Oleksandr Diachenko > > For cases when user issues COUNT(*) queries without WHERE clause PXF should > be able to leverage file-level stats for a ORC file and emit given number of > records back to HAWQ, avoiding reading actual tuples from disk. This should > be a first step in enabling PXF to use ORC stats(file, stripe and row group > levels) so we can improve a wider range of aggregate queries. > So whenever PXF receives "count" as AGG-TYPE parameters value - it should > optimize it by emitting tuples using ORC file-level stats. -- This message was sent by Atlassian JIRA (v6.3.15#6346)