Simple Query With Complex Type of MAP

Hi,

I have a simple question about querying complex types.  The schema, raw table and desired result is listed below.  Could someone help me craft this query in Impala? CDH 5.15

I can get it to work in Hive, but it seems like Impala uses a join-like syntax to access complex columns.  Many Thanks!!

schema:
snum int
items map<string, float>


raw parquet table:
1, {"a": 1.3, "b", 9.1}
2, {"c", 84.9, "b", 1.1}
3, {}
4, {"x", 42.5,"p", 0.08}


desired result:
1,a,1.3
1,b,9.1
2,c,84.9
2,b,1.1
3,null,null
4,x,42.5
4,p,0.08