[CALCITE-6374] LatticeSuggester throw NullPointerException when agg call covered with cast

• Type: Bug
• Status: Open
• Priority: Critical
• Resolution: Unresolved
• Component/s: core
• Assignee: Unassigned
• Reporter: allendang
• Created: 18/Apr/24 13:44
• Updated: 23/Apr/24 03:19

Description

I changed q1 in org.apache.calcite.materialize.LatticeSuggesterTest#testExpressionEvolution

It was originally like this

select
  "num_children_at_home" + 10 as "n10",
  "num_children_at_home" + 14 as "n14",
  sum("num_children_at_home" + 12) as "n12",
  sum("num_children_at_home" + 13) as "n13"
from "customer"
group by "num_children_at_home" + 10,   "num_children_at_home" + 14 

i changed it like following

select
  "num_children_at_home" + 10 as "n10",
  "num_children_at_home" + 14 as "n14",
  cast(sum("num_children_at_home" + 12) as double) as "n12",
  sum("num_children_at_home" + 13) as "n13"
from "customer"
group by "num_children_at_home" + 10,   "num_children_at_home" + 14 

Re-running the test case throws the following exception

measure.name
java.lang.NullPointerException: measure.name
    at java.util.Objects.requireNonNull(Objects.java:228)
    at org.apache.calcite.materialize.LatticeSuggester.deriveAlias(LatticeSuggester.java:290)
    at org.apache.calcite.materialize.LatticeSuggester.lambda$addFrame$3(LatticeSuggester.java:250)
    at org.apache.calcite.util.Util$TransformingList.get(Util.java:2810)
    at java.util.AbstractList$Itr.next(AbstractList.java:358)
    at java.util.AbstractCollection.toArray(AbstractCollection.java:141)
    at com.google.common.collect.ImmutableList.copyOf(ImmutableList.java:265)
    at com.google.common.collect.ImmutableList.copyOf(ImmutableList.java:238)
    at org.apache.calcite.materialize.Lattice$Measure.<init>(Lattice.java:567)
    at org.apache.calcite.materialize.LatticeSuggester.addFrame(LatticeSuggester.java:240) 
    at org.apache.calcite.materialize.LatticeSuggester.lambda$addQuery$1(LatticeSuggester.java:143)
    at java.util.ArrayList.forEach(ArrayList.java:1259)
    at org.apache.calcite.materialize.LatticeSuggester.addQuery(LatticeSuggester.java:143)
    at org.apache.calcite.materialize.LatticeSuggesterTest$Tester.addQuery(LatticeSuggesterTest.java:851)
    at org.apache.calcite.materialize.LatticeSuggesterTest.testExpressionEvolution(LatticeSuggesterTest.java:551)