[FLINK-7922] leastRestrictive in FlinkTypeFactory does not resolve composite type correctly

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.4.0
• Fix Version/s: 1.3.4, 1.4.0, 1.5.0
• Component/s: Table SQL / API
• Assignee: Rong Rong
• Reporter: Rong Rong
• Created: 25/Oct/17 18:13
• Updated: 19/Sep/19 19:16
• Resolved: 12/Mar/18 15:42

Description

FlinkTypeFactory does not override the following function correctly:

def leastRestrictive(types: util.List[RelDataType]): RelDataType = {
  //... 
}

dealing with SQL such as:

CASE 
  WHEN <CONDITION> THEN 
    <COMPOSITE_TYPE> 
  ELSE 
    NULL 
END

will trigger runtime exception.

See following test sample for more details:
https://github.com/walterddr/flink/commit/a5f2affc9bbbd50f06200f099c90597e519e9170

Issue Links

• links to: GitHub Pull Request #4929