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SDB is a persistence layer for use with Apache Jena that uses an SQL database to store triples/quads.

There is a newer version: 3.17.0

/*
 * 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.jena.sdb.layout2.hash;

import org.apache.jena.sdb.sql.SDBConnection ;
import org.apache.jena.sdb.store.TableDesc ;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class TupleLoaderHashDerby extends TupleLoaderHashBase {
	
	private static Logger log = LoggerFactory.getLogger(TupleLoaderHashDerby.class);
	
	public TupleLoaderHashDerby(SDBConnection connection, TableDesc tableDesc,
			int chunkSize) {
		super(connection, tableDesc, chunkSize);
	}
	
	// A compromise. Derby's temporary tables are limited, but cleaning up afterwards is worse
	@Override
    public String[] getNodeColTypes() {
		return new String[] {"BIGINT", "VARCHAR (32672)", "VARCHAR(1024)", "VARCHAR(1024)", "INT"};
	}
	
	@Override
    public String getTupleColType() {
		return "BIGINT";
	}
	
	@Override
    public String[] getCreateTempTable() {
		return new String[] { "DECLARE GLOBAL TEMPORARY TABLE" , "ON COMMIT DELETE ROWS NOT LOGGED" };
	}
	
	// We have to qualify the temporary table names
	@Override
	public String getNodeLoader() {
		return "SESSION." + super.getNodeLoader();
	}
	
	@Override
	public String getTupleLoader() {
		return "SESSION." + super.getTupleLoader();
	}
	
	@Override
	public boolean clearsOnCommit() { return true; }
}