Query optimization

Materialized WITH clause now supported using EE5 temp relation

Previously, Vertica implemented WITH clauses by either rewriting WITH statements using subqueries, or materializing WITH queries into local temp tables. By default, Vertica now executes WITH clause queries in sections of a multi-part plan and saves their output in EE5 temp relations. This update improves overall performance of WITH clauses. To learn more, see Materialization of WITH Clause.