[FLINK-11243] GroupBy udf() can not be select in TableAPI

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 1.8.0
• Component/s: Table SQL / API
• Assignee: Dian Fu
• Reporter: sunjincheng
• Created: 01/Jan/19 10:02
• Updated: 03/Jan/19 02:04
• Resolved: 03/Jan/19 02:04

Description

The group key can not be select in the follows TableAPI:

val result = order
  .groupBy('o_time.substring(1, 16))
  .select('o_time.substring(1, 16), 'o_id.count)

Exception:

org.apache.flink.table.api.ValidationException: Cannot resolve field [o_time] given input [('o_time).substring(1, 16), TMP_0].

at org.apache.flink.table.plan.logical.LogicalNode.failValidation(LogicalNode.scala:156)

BTW, We can only use the following description to avoid the above problem.

val result = order
  .select('o_id, 'c_id, 'o_time.substring(1, 16) as 'key)
  .groupBy('key)
  .select('key, 'o_id.count)

But I think it is better to make `groupby udf()` can be select in TableAPI. What do you think?

Issue Links

• is duplicated by: FLINK-6101 GroupBy fields with arithmetic expression (include UDF) can not be selected