nizhikov commented on a change in pull request #6963: IGNITE-9732: [Spark] Add joins to Spark Dataframe examples URL: https://github.com/apache/ignite/pull/6963#discussion_r336724403
########## File path: examples/src/main/spark/org/apache/ignite/examples/spark/IgniteDataFrameJoinExample.scala ########## @@ -0,0 +1,176 @@ +/* + * 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.ignite.examples.spark + +import java.lang.{Integer => JInt, Long => JLong, String => JString} + +import org.apache.ignite.cache.query.SqlFieldsQuery +import org.apache.ignite.configuration.CacheConfiguration +import org.apache.ignite.spark.IgniteDataFrameSettings._ +import org.apache.ignite.{Ignite, Ignition} +import org.apache.log4j.{Level, Logger} +import org.apache.spark.sql.SparkSession + +/** + * Example application demonstrates the join operations between two dataframes or Spark tables with data saved in Ignite caches. + */ +object IgniteDataFrameJoinExample extends App { + /** + * Ignite config file. + */ + private val CONFIG = "examples/config/example-ignite.xml" + + /** + * Test cache name. + */ + private val CACHE_NAME = "testCache" + + //Starting Ignite server node. + val ignite = setupServerAndData + + closeAfter(ignite) { ignite ⇒ + //Creating spark session. + implicit val spark = SparkSession.builder() + .appName("IgniteDataFrameJoinExample") + .master("local") + .config("spark.executor.instances", "2") + .getOrCreate() + + // Adjust the logger to exclude the logs of no interest. + Logger.getRootLogger.setLevel(Level.ERROR) + Logger.getLogger("org.apache.ignite").setLevel(Level.INFO) + + // Executing examples. + + sparkDSLJoinExample + nativeSparkSqlJoinExample + } + + /** + * Examples of usage Ignite DataFrame implementation. + * Selecting data throw Spark DSL. + * + * @param spark SparkSession. + */ + def sparkDSLJoinExample(implicit spark: SparkSession): Unit = { + println("Querying using Spark DSL.") + println + + val persons = spark.read + .format(FORMAT_IGNITE) + .option(OPTION_TABLE, "person") + .option(OPTION_CONFIG_FILE, CONFIG) + .load() + + persons.printSchema() + persons.show() + + val cities = spark.read + .format(FORMAT_IGNITE) + .option(OPTION_TABLE, "city") + .option(OPTION_CONFIG_FILE, CONFIG) + .load() + + persons.printSchema() + persons.show() + + val joinResult = persons.join(cities, persons("city_id") === cities("id")) + .select(persons("name").as("person"), persons("age"), cities("name").as("city"), cities("country")) + + joinResult.explain(true) + joinResult.printSchema() + joinResult.show() + } + + /** + * Examples of usage Ignite DataFrame implementation. Review comment: Javadoc not formatted properly. ---------------------------------------------------------------- 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
