xuefuz commented on a change in pull request #8859: [FLINK-12905][table-planner] Enable querying CatalogViews in legacy planner URL: https://github.com/apache/flink/pull/8859#discussion_r323991723
########## File path: flink-table/flink-table-planner/src/main/java/org/apache/flink/table/planner/FlinkViewTable.java ########## @@ -0,0 +1,65 @@ +/* + * 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.planner; + +import org.apache.flink.table.api.SqlDialect; +import org.apache.flink.table.api.TableConfig; +import org.apache.flink.table.api.ValidationException; + +import org.apache.calcite.plan.RelOptTable; +import org.apache.calcite.rel.RelNode; +import org.apache.calcite.rel.type.RelProtoDataType; +import org.apache.calcite.schema.impl.ViewTable; + +import java.util.List; + +import static org.apache.flink.util.Preconditions.checkNotNull; + +/** + * Thin extension to {@link ViewTable} that performs {@link SqlDialect} check + * before expanding the view. It throws exception if the view's dialect is different + * from configured in the {@link TableConfig}. + */ +public class FlinkViewTable extends ViewTable { + private final SqlDialect viewDialect; + + public FlinkViewTable( + SqlDialect viewDialect, + RelProtoDataType rowType, + String viewSql, + List<String> schemaPath, + List<String> viewPath) { + super(null, rowType, viewSql, schemaPath, viewPath); + this.viewDialect = checkNotNull(viewDialect); + } + + @Override + public RelNode toRel(RelOptTable.ToRelContext context, RelOptTable relOptTable) { + TableConfig tableConfig = context.getCluster().getPlanner().getContext().unwrap(TableConfig.class); + SqlDialect sqlDialect = tableConfig.getSqlDialect(); + if (!viewDialect.equals(sqlDialect)) { Review comment: It's fine if we reject Hive views if the current dialect isn't set to Hive. However, we need to consider the case that a Hive view is created by other tools, where the dialect info isn't specifically set. Not sure if this should be covered in this PR, but Hive views created by Flink needs to be understandable by other Hive-compatible tools. To do that, cross-catalog views are not good for Hive. Catalog-prefix also needs to be trimmed from the expanded query. ---------------------------------------------------------------- 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
