Github user mccheah commented on a diff in the pull request:
https://github.com/apache/spark/pull/23086#discussion_r236500170
--- Diff: sql/core/src/main/java/org/apache/spark/sql/sources/v2/Table.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;
+
+import org.apache.spark.annotation.Evolving;
+import org.apache.spark.sql.sources.v2.reader.Scan;
+import org.apache.spark.sql.sources.v2.reader.ScanBuilder;
+import org.apache.spark.sql.types.StructType;
+
+/**
+ * An interface representing a logical structured data set of a data
source. For example, the
+ * implementation can be a directory on the file system, a topic of Kafka,
or a table in the
+ * catalog, etc.
+ *
+ * This interface can mixin the following interfaces to support different
operations:
+ * <ul>
+ * <li>{@link SupportsBatchRead}: this table can be read in batch
queries.</li>
+ * </ul>
+ */
+@Evolving
+public interface Table {
+
+ /**
+ * Returns the schema of this table.
+ */
+ StructType schema();
+
+ /**
+ * Returns a {@link ScanBuilder} which can be used to build a {@link
Scan} later. Spark will call
+ * this method for each data scanning query.
+ *
+ * The builder can take some query specific information to do operators
pushdown, and keep these
+ * information in the created {@link Scan}.
+ */
+ ScanBuilder newScanBuilder(DataSourceOptions options);
--- End diff --
Makes sense to me - `DataSourceOptions` was carrying along identifiers that
really belong to a table identifier and that should be interpreted at the
catalog level, not the data read level. In other words the implementation of
this `Table` should already know _what_ locations to look up (e.g. "files
comprising dataset D"), now it's a matter of _how_ (e.g. pushdown, filter
predicates).
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