asterix-app/src/test/resources/demo_aql/local/110-self-join-dblp.aql

/*
 * 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
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 */
use dataverse demo_aql;

declare type DBLPType as open {
 id: int32,
 dblpid: string,
 title: string,
 authors: string,
 misc: string
}

declare nodegroup group1 on asterix_nc1, asterix_nc2;

declare dataset DBLP(DBLPType) 
  primary key id on group1;

write output to asterix_nc1:"/tmp/110-self-join-dblp.adm";

set simthreshold '.5f';

for $k in (
  for $i in dataset('DBLP')
  for $j in dataset('DBLP')
  where $i.title ~= $j.title
  order by $i.id, $j.id
  return {'dblp1': $i, 'dblp2': $j}
) 
where $k.dblp1.id < $k.dblp2.id
return $k