/*
* 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.
*/
/**
* <strong>Table API (Java)</strong><br>
*
* A {@link org.apache.flink.table.api.java.BatchTableEnvironment} can be used to create a
* {@link org.apache.flink.table.api.Table} from a {@link org.apache.flink.api.java.DataSet}.
* Equivalently, a {@link org.apache.flink.table.api.java.StreamTableEnvironment} can be used to
* create a {@link org.apache.flink.table.api.Table} from a
* {@link org.apache.flink.streaming.api.datastream.DataStream}.
*
* <p>
* Tables can be used to perform SQL-like queries on data. Please have
* a look at {@link org.apache.flink.table.api.Table} to see which operations are supported and
* how query strings are written.
*
* <p>
* Example:
*
* <pre>{@code
* ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
* BatchTableEnvironment tEnv = TableEnvironment.getTableEnvironment(env);
*
* DataSet<WC> input = env.fromElements(
* new WC("Hello", 1),
* new WC("Ciao", 1),
* new WC("Hello", 1));
*
* Table table = tEnv.fromDataSet(input);
*
* Table filtered = table
* .groupBy("word")
* .select("word.count as count, word")
* .filter("count = 2");
*
* DataSet<WC> result = tEnv.toDataSet(filtered, WC.class);
*
* result.print();
* }</pre>
*
* <p>
* As seen above, a {@link org.apache.flink.table.api.Table} can be converted back to the
* underlying API representation using
* {@link org.apache.flink.table.api.java.BatchTableEnvironment#toDataSet(Table, java.lang.Class)},
* {@link org.apache.flink.table.api.java.StreamTableEnvironment#toAppendStream(Table, java.lang.Class)}}, or
* {@link org.apache.flink.table.api.java.StreamTableEnvironment#toRetractStream(Table, java.lang.Class)}}.
*/
package org.apache.flink.table.api.java;
import org.apache.flink.table.api.Table;