Github user Vlad-Storona commented on a diff in the pull request:

    https://github.com/apache/drill/pull/774#discussion_r148567585
  
    --- Diff: contrib/storage-opentsdb/src/main/java/org/apache/drill/exec/store/openTSDB/DrillOpenTSDBTable.java ---
    @@ -0,0 +1,69 @@
    +/*
    + * 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.drill.exec.store.openTSDB;
    +
    +import com.google.common.collect.Lists;
    +import org.apache.calcite.rel.type.RelDataType;
    +import org.apache.calcite.rel.type.RelDataTypeFactory;
    +import org.apache.calcite.sql.type.SqlTypeName;
    +import org.apache.drill.exec.planner.logical.DynamicDrillTable;
    +import org.apache.drill.exec.store.openTSDB.client.OpenTSDBTypes;
    +import org.apache.drill.exec.store.openTSDB.client.Schema;
    +import org.apache.drill.exec.store.openTSDB.dto.ColumnDTO;
    +
    +import java.util.List;
    +
    +public class DrillOpenTSDBTable extends DynamicDrillTable {
    +
    +  private final Schema schema;
    +
    +  public DrillOpenTSDBTable(String storageEngineName, OpenTSDBStoragePlugin plugin, Schema schema, OpenTSDBScanSpec scanSpec) {
    +    super(plugin, storageEngineName, scanSpec);
    +    this.schema = schema;
    +  }
    +
    +  @Override
    +  public RelDataType getRowType(final RelDataTypeFactory typeFactory) {
    +    List<String> names = Lists.newArrayList();
    +    List<RelDataType> types = Lists.newArrayList();
    +    convertToRelDataType(typeFactory, names, types);
    +    return typeFactory.createStructType(types, names);
    +  }
    +
    +  private void convertToRelDataType(RelDataTypeFactory typeFactory, List<String> names, List<RelDataType> types) {
    +    for (ColumnDTO column : schema.getColumns()) {
    +      names.add(column.getColumnName());
    +      RelDataType type = getSqlTypeFromOpenTSDBType(typeFactory, column.getColumnType());
    +      type = typeFactory.createTypeWithNullability(type, column.isNullable());
    +      types.add(type);
    +    }
    +  }
    +
    +  private RelDataType getSqlTypeFromOpenTSDBType(RelDataTypeFactory typeFactory, OpenTSDBTypes type) {
    +    switch (type) {
    +      case STRING:
    +        return typeFactory.createSqlType(SqlTypeName.VARCHAR, Integer.MAX_VALUE);
    +      case DOUBLE:
    +        return typeFactory.createSqlType(SqlTypeName.DOUBLE);
    +      case TIMESTAMP:
    +        return typeFactory.createSqlType(SqlTypeName.TIMESTAMP);
    +      default:
    +        throw new UnsupportedOperationException("Unsupported type.");
    --- End diff --
    
    Sure, I will add information about unsupported types to the exception message.


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