[CALCITE-3673] ListTransientTable should not leave tables in the schema

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.21.0
• Fix Version/s: 1.30.0
• Component/s: core
• Labels: pull-request-available
• Assignee: Ruben Q L
• Reporter: Vladimir Sitnikov
• Created: 03/Jan/20 11:22
• Updated: 19/Mar/22 09:21
• Resolved: 18/Feb/22 15:11

Description

1) org.apache.calcite.schema.impl.ListTransientTable#scan adds itself to a schema: root.getRootSchema().add(name, this); however, it misses cleanup, so it looks like a memory leak

2) ListTransientTable is not implementable with EnumerableTableScan as org.apache.calcite.tools.RelBuilder#transientScan(java.lang.String, org.apache.calcite.rel.type.RelDataType) is using org.apache.calcite.prepare.RelOptTableImpl#create(org.apache.calcite.plan.RelOptSchema, org.apache.calcite.rel.type.RelDataType, org.apache.calcite.schema.Table, com.google.common.collect.ImmutableList<java.lang.String>) which creates RelOptTableImpl with NULL expressionFunction which means org.apache.calcite.prepare.RelOptTableImpl#getExpression returns null

Issue Links

• is caused by: CALCITE-2812 Add algebraic operators to allow expressing recursive queries
• relates to: CALCITE-3677 Add assertion to EnumerableTableScan constructor to validate if the table is suitable for enumerable scan
• relates to: CALCITE-4054 RepeatUnion containing a Correlate with a transientScan on its RHS causes NPE
• links to: GitHub Pull Request #1721
• links to: GitHub Pull Request #2690