Vladimir Sitnikov created CALCITE-4222: ------------------------------------------
Summary: Clarify if null elements are allowed in RelTraitSet Key: CALCITE-4222 URL: https://issues.apache.org/jira/browse/CALCITE-4222 Project: Calcite Issue Type: Sub-task Components: core Affects Versions: 1.25.0 Reporter: Vladimir Sitnikov Currently, one-half of the methods in {{RelTraitSet}} fails with NPE, and another half does have some null-checks. Then there are {{getDefault()}} and {{isDefault()}} AFAIK the only way to create a traitset with null element currently is to implement {{org.apache.calcite.plan.RelTraitDef#getDefault}} to return {{null}} (which never happens in Calcite code). However, such a traitset would likely fail with NPE in {{org.apache.calcite.plan.RelTraitSet#satisfies}} quite fast. {{RelCollationTraitDef}} and {{RelDistributionTraitDef}} have non-null default value which might interfere with collation and distribution metadata. For instance, {{distribution}} metadata might return null, and then it would fail with NPE when replacing distribution trait. -- This message was sent by Atlassian Jira (v8.3.4#803005)