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Vladimir Sitnikov commented on CALCITE-4215: -------------------------------------------- One of the issues is {{double org.apache.calcite.rel.RelNode#estimateRowCount(RelMetadataQuery mq)}}. In other words the method must return non-nullable double, however it is often implemented as {{mq.getRowCount(...)}}. If metadata can return nullable rowCount, then it must be converted to non-nullable {{double}} somehow. So either we deprecate {{double estimateRowCount}} method and create {{Double estimateRowCount}}, or we go with {{getRowCount}} / {{getRowCountOrNull}} in the metadata class. > Ensure org.apache.calcite.schema.Statistic uses null vs emptyList > appropriately > ------------------------------------------------------------------------------- > > Key: CALCITE-4215 > URL: https://issues.apache.org/jira/browse/CALCITE-4215 > Project: Calcite > Issue Type: Sub-task > Components: core > Affects Versions: 1.25.0 > Reporter: Vladimir Sitnikov > Priority: Major > Labels: pull-request-available > Time Spent: 10m > Remaining Estimate: 0h > > null: statistic is *not* *known* > emptyList: statistic is *known*, and the value is *empty* (e.g. no unique > keys in the table) -- This message was sent by Atlassian Jira (v8.3.4#803005)