| /* |
| * 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.druid.sql.calcite.table; |
| |
| import com.google.common.base.Preconditions; |
| import org.apache.calcite.plan.RelOptTable; |
| import org.apache.calcite.plan.RelOptTable.ToRelContext; |
| import org.apache.calcite.rel.RelNode; |
| import org.apache.calcite.rel.logical.LogicalTableScan; |
| import org.apache.druid.query.DataSource; |
| import org.apache.druid.query.InlineDataSource; |
| |
| /** |
| * Represents a specialized table used within Druid's Calcite-based planner. |
| * Used in {@link org.apache.druid.sql.calcite.rule.DruidLogicalValuesRule DruidLogicalValuesRule} |
| * to implement trivial {@code SELECT 1} style queries that return constant values represented |
| * by this inline table. |
| */ |
| public class InlineTable extends DruidTable |
| { |
| private final DataSource dataSource; |
| |
| public InlineTable(final InlineDataSource dataSource) |
| { |
| super(dataSource.getRowSignature()); |
| this.dataSource = Preconditions.checkNotNull(dataSource, "dataSource"); |
| } |
| |
| @Override |
| public DataSource getDataSource() |
| { |
| return dataSource; |
| } |
| |
| @Override |
| public boolean isJoinable() |
| { |
| return false; |
| } |
| |
| @Override |
| public boolean isBroadcast() |
| { |
| return false; |
| } |
| |
| @Override |
| public RelNode toRel(ToRelContext context, RelOptTable table) |
| { |
| return LogicalTableScan.create(context.getCluster(), table, context.getTableHints()); |
| } |
| |
| @Override |
| public String toString() |
| { |
| return "DatasourceMetadata{" + |
| "dataSource=" + dataSource + |
| ", rowSignature=" + getRowSignature() + |
| '}'; |
| } |
| } |