[CALCITE-4210] Sub-query in ON clause is not correctly expanded by SqlToRelConverter

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.26.0
• Component/s: core
• Labels: pull-request-available
• Assignee: Unassigned
• Reporter: James Starr
• Created: 01/Sep/20 22:29
• Updated: 31/Mar/21 20:03
• Resolved: 30/Sep/20 03:47

Description

SqlToRelConverter does not correctly expand a sub-query in an ON clause. Aggregation is dropped during decorrelation.

SELECT "employee"."department_id", "employee"."salary"
FROM "department"
LEFT JOIN "employee" ON "employee"."salary" = (
  SELECT max("employee"."salary")
  FROM "employee"
  WHERE  "employee"."department_id" = "department"."department_id"
)

LogicalProject(department_id=[$9], salary=[$13])
  LogicalJoin(condition=[=($13, $0)], joinType=[left])
    LogicalTableScan(table=[[foodmart, department]])
    LogicalTableScan(table=[[foodmart, employee]])

This may be related to CALCITE-4206.

Issue Links

• incorporates: CALCITE-1045 Decorrelate sub-queries in Project and Join
• is related to: CALCITE-1757 Convert sub-query to windowed aggregate function ("WinMagic")
• relates to: CALCITE-4100 Join plan with select MAX subquery drops MAX operator
• links to: GitHub Pull Request #2138