| /* |
| * 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.wayang.jdbc.operators; |
| |
| import java.sql.Connection; |
| import java.util.Collections; |
| import java.util.List; |
| import org.apache.wayang.basic.operators.TableSource; |
| import org.apache.wayang.core.plan.wayangplan.ExecutionOperator; |
| import org.apache.wayang.core.platform.ChannelDescriptor; |
| import org.apache.wayang.jdbc.compiler.FunctionCompiler; |
| import org.apache.wayang.jdbc.platform.JdbcPlatformTemplate; |
| |
| public interface JdbcExecutionOperator extends ExecutionOperator { |
| |
| /** |
| * Creates a SQL clause for this instance. For {@link TableSource}s it returns an identifier for the table |
| * usable in a {@code FROM} clause. For {@link JdbcProjectionOperator}s it returns a list usable in a |
| * {@code SELECT} clause. For {@link JdbcFilterOperator}s it creates a condition usable in a {@code WHERE} clause. |
| * Also, these different clauses should be compatible for connected {@link JdbcExecutionOperator}s. |
| * |
| * @param compiler used to create SQL code |
| * @return the SQL clause |
| */ |
| String createSqlClause(Connection connection, FunctionCompiler compiler); |
| |
| @Override |
| JdbcPlatformTemplate getPlatform(); |
| |
| @Override |
| default List<ChannelDescriptor> getSupportedInputChannels(int index) { |
| return Collections.singletonList(this.getPlatform().getSqlQueryChannelDescriptor()); |
| } |
| |
| @Override |
| default List<ChannelDescriptor> getSupportedOutputChannels(int index) { |
| return Collections.singletonList(this.getPlatform().getSqlQueryChannelDescriptor()); |
| } |
| |
| } |