Dongjoon Hyun created SPARK-25823:
-------------------------------------
Summary: map_filter can generate incorrect data
Key: SPARK-25823
URL: https://issues.apache.org/jira/browse/SPARK-25823
Project: Spark
Issue Type: Bug
Components: SQL
Affects Versions: 2.4.0
Reporter: Dongjoon Hyun
This is not a regression because this occurs in new high-order functions like
`map_filter` and `map_concat`. The root cause is Spark's `CreateMap` allows the
duplication. If we want to allow this difference in new high-order functions,
we had better add some warning about this different on these functions after
RC4 voting at least. Otherwise, this will surprise Presto-based users.
*Spark 2.4*
{code:java}
spark-sql> CREATE TABLE t AS SELECT m, map_filter(m, (k,v) -> v=2) c FROM
(SELECT map_concat(map(1,2), map(1,3)) m);
spark-sql> SELECT * FROM t;
{1:3} {1:2}
{code}
*Presto 0.212*
{code:java}
presto> SELECT a, map_filter(a, (k,v) -> v = 2) FROM (SELECT
map_concat(map(array[1],array[2]), map(array[1],array[3])) a);
a | _col1
-------+-------
{1=3} | {}
{code}
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
