Github user gatorsmile commented on a diff in the pull request:
https://github.com/apache/spark/pull/20153#discussion_r160747322
--- Diff:
sql/core/src/main/java/org/apache/spark/sql/sources/v2/reader/SupportsScanColumnarBatch.java
---
@@ -0,0 +1,51 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.sql.sources.v2.reader;
+
+import java.util.List;
+
+import org.apache.spark.annotation.InterfaceStability;
+import org.apache.spark.sql.Row;
+import org.apache.spark.sql.vectorized.ColumnarBatch;
+
+/**
+ * A mix-in interface for {@link DataSourceV2Reader}. Data source readers
can implement this
+ * interface to output {@link ColumnarBatch} and make the scan faster.
+ */
[email protected]
+public interface SupportsScanColumnarBatch extends DataSourceV2Reader {
+ @Override
+ default List<ReadTask<Row>> createReadTasks() {
+ throw new IllegalStateException(
+ "createReadTasks should not be called with
SupportsScanColumnarBatch.");
+ }
+
+ /**
+ * Similar to {@link DataSourceV2Reader#createReadTasks()}, but returns
columnar data in batches.
+ */
+ List<ReadTask<ColumnarBatch>> createBatchReadTasks();
+
+ /**
+ * A safety door for columnar batch reader. It's possible that the
implementation can only support
+ * some certain columns with certain types. Users can overwrite this
method and
+ * {@link #createReadTasks()} to fallback to normal read path under some
conditions.
+ */
+ default boolean enableBatchRead() {
--- End diff --
This name is more general. It looks fine to me. In the future, if we
support another batch read mode, we can add the extra function to further
identify the batch mode.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
