jeyhunkarimov commented on code in PR #23612: URL: https://github.com/apache/flink/pull/23612#discussion_r1446686365
########## flink-table/flink-table-planner/src/main/java/org/apache/flink/table/planner/operations/converters/SqlShowDatabasesConverter.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.flink.table.planner.operations.converters; + +import org.apache.flink.sql.parser.dql.SqlShowDatabases; +import org.apache.flink.table.catalog.CatalogManager; +import org.apache.flink.table.operations.Operation; +import org.apache.flink.table.operations.ShowDatabasesOperation; + +/** A converter for {@link SqlShowDatabases}. */ +public class SqlShowDatabasesConverter implements SqlNodeConverter<SqlShowDatabases> { + + @Override + public Operation convertSqlNode(SqlShowDatabases sqlShowDatabases, ConvertContext context) { + if (sqlShowDatabases.getPreposition() == null) { + return new ShowDatabasesOperation( + sqlShowDatabases.getLikeType(), + sqlShowDatabases.getLikeSqlPattern(), + sqlShowDatabases.isNotLike()); + } else { + CatalogManager catalogManager = context.getCatalogManager(); + String[] fullCatalogName = sqlShowDatabases.getCatalog(); + String catalogName = + fullCatalogName.length == 0 + ? catalogManager.getCurrentCatalog() + : fullCatalogName[0]; Review Comment: That is also what we do. If no catalog is provided, summary string outputs no catalog name: ``` final String sql1 = "SHOW DATABASES"; assertShowDatabases(sql1, sql1); ``` The thing is if a user provides a catalog name, it does not necessarily execute the `ShowDatabaseOperation::execute(Context ctx)` method. For example, please see the below code snipped I used in tests. ``` private void assertShowDatabases(String sql, String expectedSummary) { Operation operation = parse(sql); assertThat(operation).isInstanceOf(ShowDatabasesOperation.class); final ShowDatabasesOperation showDatabasesOperation = (ShowDatabasesOperation) operation; assertThat(showDatabasesOperation.asSummaryString()).isEqualTo(expectedSummary); } ``` Moreover, we the catalog name provided in the constructor (`ShowDatabaseOperation`) is not necessarily the same as the one we obtain in `ShowDatabaseOperation::execute(Context ctx)`. That is why, we retrieve the catalog only if the `catalogName` is `null`: ``` String cName = catalogName == null ? ctx.getCatalogManager().getCurrentCatalog() : catalogName; ``` -- 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. To unsubscribe, e-mail: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
