Github user Ben-Zvi commented on a diff in the pull request:
https://github.com/apache/drill/pull/1101#discussion_r164549701
--- Diff:
exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/aggregate/HashAggBatch.java
---
@@ -255,7 +254,6 @@ private HashAggregator createAggregatorInternal()
throws SchemaChangeException,
groupByOutFieldIds[i] = container.add(vv);
}
- int extraNonNullColumns = 0; // each of SUM, MAX and MIN gets an extra
bigint column
--- End diff --
Why was this removed ? Unfortunately the code generator still generates an
internal Bigint column to keep the "not null" status of the Aggregated Values,
in the cases of sum/max/min. Below is an example of a generated code (returning
a nullable varchar) - note the nonNullCount (see DRILL-5728):
```
public void outputRecordValues(int htRowIdx, int outRowIdx)
throws SchemaChangeException
{
{
NullableVarCharHolder out17;
{
final NullableVarCharHolder out = new
NullableVarCharHolder();
vv1 .getAccessor().get((htRowIdx), work0);
ObjectHolder value = work0;
work4 .value = vv5 .getAccessor().get((htRowIdx));
UInt1Holder init = work4;
work8 .value = vv9 .getAccessor().get((htRowIdx));
BigIntHolder nonNullCount = work8;
DrillBuf buf = work12;
MaxVarBytesFunctions$NullableVarCharMax_output: {
if (nonNullCount.value > 0) {
out.isSet = 1;
org.apache.drill.exec.expr.fn.impl.DrillByteArray tmp =
(org.apache.drill.exec.expr.fn.impl.DrillByteArray) value.obj;
buf = buf.reallocIfNeeded(tmp.getLength());
buf.setBytes(0, tmp.getBytes(), 0, tmp.getLength());
out.start = 0;
out.end = tmp.getLength();
out.buffer = buf;
} else
{
out.isSet = 0;
}
}
work0 = value;
vv1 .getMutator().setSafe((htRowIdx), work0);
work4 = init;
vv5 .getMutator().set((htRowIdx), work4 .value);
work8 = nonNullCount;
vv9 .getMutator().set((htRowIdx), work8 .value);
work12 = buf;
out17 = out;
}
if (!(out17 .isSet == 0)) {
vv18 .getMutator().setSafe((outRowIdx), out17 .isSet,
out17 .start, out17 .end, out17 .buffer);
}
}
}
```
---
