bowenli86 commented on a change in pull request #8404: [FLINK-11476][table] Create CatalogManager to manage multiple catalogs URL: https://github.com/apache/flink/pull/8404#discussion_r283595427
########## File path: flink-table/flink-table-planner/src/main/java/org/apache/flink/table/catalog/CatalogManagerSchema.java ########## @@ -0,0 +1,122 @@ +/* + * 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.flink.table.catalog; + +import org.apache.flink.annotation.Internal; +import org.apache.flink.table.api.CatalogNotExistException; + +import org.apache.calcite.linq4j.tree.Expression; +import org.apache.calcite.rel.type.RelProtoDataType; +import org.apache.calcite.schema.Function; +import org.apache.calcite.schema.Schema; +import org.apache.calcite.schema.SchemaPlus; +import org.apache.calcite.schema.SchemaVersion; +import org.apache.calcite.schema.Table; + +import java.util.Collection; +import java.util.Collections; +import java.util.LinkedHashSet; +import java.util.Set; +import java.util.stream.Collectors; +import java.util.stream.Stream; + +/** + * Bridge between {@link CatalogManager} and {@link Schema}. This way we can query Flink's specific catalogs + * from Calcite. + * + * <p>The mapping for {@link Catalog}s is modeled as a strict two-level reference structure for Flink in Calcite, + * the full path of tables and views is of format [catalog_name].[db_name].[meta-object_name]. + * + * <p>It also supports {@link ExternalCatalog}s. An external catalog maps 1:1 to Calcite's schema. + */ +@Internal +public class CatalogManagerSchema implements Schema { Review comment: can we use a better name for this class? Not sure if we should support ExternalCatalog yet, but even if we do, its naming has been a bit confusing ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
