Github user yhuai commented on a diff in the pull request:
https://github.com/apache/spark/pull/14753#discussion_r76152853
--- Diff:
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/aggregate/interfaces.scala
---
@@ -389,3 +389,144 @@ abstract class DeclarativeAggregate
def right: AttributeReference =
inputAggBufferAttributes(aggBufferAttributes.indexOf(a))
}
}
+
+/**
+ * Aggregation function which allows **arbitrary** user-defined java
object to be used as internal
+ * aggregation buffer object.
+ *
+ * {{{
+ * aggregation buffer for normal aggregation function `avg`
+ * |
+ * v
+ *
+--------------+---------------+-----------------------------------+
+ * | sum1 (Long) | count1 (Long) | generic user-defined
java objects |
+ *
+--------------+---------------+-----------------------------------+
+ * ^
+ * |
+ * Aggregation buffer object for
`TypedImperativeAggregate` aggregation function
+ * }}}
--- End diff --
Let's also add a normal agg buffer after the generic one. So, readers will
not assume that generic ones will always be put at the end.
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org
For additional commands, e-mail: reviews-h...@spark.apache.org
