Github user rxin commented on a diff in the pull request:
https://github.com/apache/spark/pull/9531#discussion_r44204792
--- Diff: sql/core/src/main/scala/org/apache/spark/sql/DataFrame.scala ---
@@ -1478,18 +1478,54 @@ class DataFrame private[sql](
/**
* Returns the first `n` rows in the [[DataFrame]].
+ *
+ * Running take requires moving data into the application's driver
process, and doing so on a
+ * very large dataset can crash the driver process with OutOfMemoryError.
+ *
* @group action
* @since 1.3.0
*/
def take(n: Int): Array[Row] = head(n)
/**
+ * Returns the first `n` rows in the [[DataFrame]] as a list.
+ *
+ * Running take requires moving data into the application's driver
process, and doing so on a
+ * very large dataset can crash the driver process with OutOfMemoryError.
+ *
+ * @group action
+ * @since 1.6.0
+ */
+ def takeAsList(n: Int): java.util.List[Row] =
java.util.Arrays.asList(take(n) : _*)
+
+ /**
* Returns an array that contains all of [[Row]]s in this [[DataFrame]].
+ *
+ * Running collect requires moving all the data into the application's
driver process, and
+ * doing so on a very large dataset can crash the driver process with
OutOfMemoryError.
+ *
+ * For Java API, use [[collectAsList]].
--- End diff --
No it doesn't' exist, but still good to use a java list.
---
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 [email protected] or file a JIRA ticket
with INFRA.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
