| /** |
| * 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.hadoop.vertica; |
| |
| import java.io.DataInput; |
| import java.io.DataOutput; |
| import java.io.IOException; |
| import java.sql.Connection; |
| import java.sql.PreparedStatement; |
| import java.sql.ResultSet; |
| import java.sql.SQLException; |
| import java.util.List; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.io.Text; |
| import org.apache.hadoop.io.Writable; |
| import org.apache.hadoop.mapreduce.InputSplit; |
| |
| /** |
| * Input split class for reading data from Vertica |
| * |
| */ |
| public class VerticaInputSplit extends InputSplit implements Writable { |
| private static final Log LOG = LogFactory.getLog(VerticaInputSplit.class); |
| |
| PreparedStatement stmt = null; |
| Connection connection = null; |
| VerticaConfiguration vtconfig = null; |
| String inputQuery = null; |
| List<Object> segmentParams = null; |
| long start = 0; |
| long end = 0; |
| |
| /** (@inheritDoc) */ |
| public VerticaInputSplit() { |
| LOG.trace("Input split default constructor"); |
| } |
| |
| /** |
| * Set the input query and a list of parameters to substitute when evaluating |
| * the query |
| * |
| * @param inputQuery |
| * SQL query to run |
| * @param segmentParams |
| * list of parameters to substitute into the query |
| * @param start |
| * the logical starting record number |
| * @param end |
| * the logical ending record number |
| */ |
| public VerticaInputSplit(String inputQuery, List<Object> segmentParams, |
| long start, long end) { |
| LOG.trace("Input split constructor with query and params"); |
| this.inputQuery = inputQuery; |
| this.segmentParams = segmentParams; |
| this.start = start; |
| this.end = end; |
| } |
| |
| /** (@inheritDoc) */ |
| public void configure(Configuration conf) throws Exception { |
| LOG.trace("Input split configured"); |
| vtconfig = new VerticaConfiguration(conf); |
| connection = vtconfig.getConnection(false); |
| connection.setAutoCommit(true); |
| connection.setTransactionIsolation(Connection.TRANSACTION_READ_COMMITTED); |
| } |
| |
| /** |
| * Return the parameters used for input query |
| * |
| * @return |
| */ |
| public List<Object> getSegmentParams() { |
| return segmentParams; |
| } |
| |
| /** |
| * Run the query that, when executed returns input for the mapper |
| * |
| * @return |
| * @throws Exception |
| */ |
| public ResultSet executeQuery() throws Exception { |
| LOG.trace("Input split execute query"); |
| long length = getLength(); |
| |
| if (length != 0) |
| inputQuery = "SELECT * FROM ( " + inputQuery |
| + " ) limited LIMIT ? OFFSET ?"; |
| |
| if (connection == null) |
| throw new Exception("Cannot execute query with no connection"); |
| stmt = connection.prepareStatement(inputQuery); |
| |
| int i = 1; |
| if (segmentParams != null) |
| for (Object param : segmentParams) |
| stmt.setObject(i++, param); |
| |
| if (length != 0) { |
| stmt.setLong(i++, length); |
| stmt.setLong(i++, start); |
| } |
| |
| ResultSet rs = stmt.executeQuery(); |
| return rs; |
| } |
| |
| /** (@inheritDoc) */ |
| public void close() throws SQLException { |
| stmt.close(); |
| } |
| |
| /** |
| * @return The index of the first row to select |
| */ |
| public long getStart() { |
| return start; |
| } |
| |
| /** |
| * @return The index of the last row to select |
| */ |
| public long getEnd() { |
| return end; |
| } |
| |
| /** |
| * @return The total row count in this split |
| */ |
| public long getLength() throws IOException { |
| // TODO: figureout how to return length when there is no start and end |
| return end - start; |
| } |
| |
| /** {@inheritDoc} */ |
| public String[] getLocations() throws IOException { |
| return new String[] {}; |
| } |
| |
| /** (@inheritDoc) */ |
| public Configuration getConfiguration() { |
| return vtconfig.getConfiguration(); |
| } |
| |
| /** {@inheritDoc} */ |
| public void readFields(DataInput in) throws IOException { |
| inputQuery = Text.readString(in); |
| long paramCount = in.readLong(); |
| if (paramCount > 0) { |
| VerticaRecord record = new VerticaRecord(); |
| record.readFields(in); |
| segmentParams = record.getValues(); |
| } |
| start = in.readLong(); |
| end = in.readLong(); |
| } |
| |
| /** {@inheritDoc} */ |
| public void write(DataOutput out) throws IOException { |
| Text.writeString(out, inputQuery); |
| if (segmentParams != null && segmentParams.size() > 0) { |
| out.writeLong(segmentParams.size()); |
| VerticaRecord record = new VerticaRecord(segmentParams, true); |
| record.write(out); |
| } else |
| out.writeLong(0); |
| out.writeLong(start); |
| out.writeLong(end); |
| } |
| } |