[CALCITE-3524] Add methods to RelBuilder to create RexSubQuery

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 1.28.0
• Component/s: core
• Labels: pull-request-available
• Assignee: Julian Hyde
• Reporter: Amir Gajst
• Created: 20/Nov/19 08:44
• Updated: 20/Oct/21 05:24
• Resolved: 15/Oct/21 00:51

Description

When building relational expressions, the simplest way is by using the RelBuilder which does not currently support creation of a RexSubQuery.
We can add RexSubQuery creation functions to the RelBuilder to make it more "visible" and convenient to use. 

Issue Links

• is related to: CALCITE-4486 UNIQUE predicate
• is related to: CALCITE-4719 Add variants of RexSubQuery that collect sub-queries into MULTISET, ARRAY and MAP collections
• links to: GitHub Pull Request #1690