[SPARK-25831] should apply "earlier entry wins" in hive map value converter

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Invalid
• Affects Version/s: 2.4.0
• Component/s: SQL
• Assignee: Unassigned
• Reporter: Wenchen Fan
• Created: 25/Oct/18 00:52
• Updated: 28/Nov/18 15:45
• Resolved: 28/Nov/18 15:45

Description

scala> sql("CREATE TABLE t AS SELECT map(1,2,1,3) as map")
res11: org.apache.spark.sql.DataFrame = []

scala> sql("select * from t").show
+--------+
|     map|
+--------+
|[1 -> 3]|
+--------+

We mistakenly apply "later entry wins"