| /** |
| * 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.sqoop.mapreduce.db; |
| |
| import java.io.IOException; |
| import java.lang.reflect.Method; |
| import java.sql.Connection; |
| import java.sql.SQLException; |
| |
| import org.apache.sqoop.SqoopOptions; |
| import org.apache.sqoop.manager.oracle.OracleUtils; |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.sqoop.mapreduce.DBWritable; |
| |
| /** |
| * A RecordReader that reads records from an Oracle SQL table. |
| */ |
| public class OracleDBRecordReader<T extends DBWritable> |
| extends DBRecordReader<T> { |
| |
| /** Configuration key to set to a timezone string. */ |
| public static final String SESSION_TIMEZONE_KEY = "oracle.sessionTimeZone"; |
| |
| private static final Log LOG = LogFactory.getLog(OracleDBRecordReader.class); |
| |
| // CHECKSTYLE:OFF |
| public OracleDBRecordReader(DBInputFormat.DBInputSplit split, |
| Class<T> inputClass, Configuration conf, Connection conn, |
| DBConfiguration dbConfig, String cond, String [] fields, |
| String table) throws SQLException { |
| super(split, inputClass, conf, conn, dbConfig, cond, fields, table); |
| setSessionTimeZone(conf, conn); |
| } |
| // CHECKSTYLE:ON |
| |
| |
| /** Returns the query for selecting the records from an Oracle DB. */ |
| protected String getSelectQuery() { |
| StringBuilder query = new StringBuilder(); |
| DBConfiguration dbConf = getDBConf(); |
| String conditions = getConditions(); |
| String tableName = getTableName(); |
| String [] fieldNames = getFieldNames(); |
| |
| // Oracle-specific codepath to use rownum instead of LIMIT/OFFSET. |
| if (dbConf.getInputQuery() == null) { |
| query.append("SELECT "); |
| |
| boolean escapingDisabled = OracleUtils.isOracleEscapingDisabled(getConf()); |
| for (int i = 0; i < fieldNames.length; i++) { |
| query.append(OracleUtils.escapeIdentifier(fieldNames[i], escapingDisabled)); |
| if (i != fieldNames.length -1) { |
| query.append(", "); |
| } |
| } |
| |
| query.append(" FROM ").append(tableName); |
| if (conditions != null && conditions.length() > 0) { |
| query.append(" WHERE ").append(conditions); |
| } |
| String orderBy = dbConf.getInputOrderBy(); |
| if (orderBy != null && orderBy.length() > 0) { |
| query.append(" ORDER BY ").append(orderBy); |
| } |
| } else { |
| //PREBUILT QUERY |
| query.append(dbConf.getInputQuery()); |
| } |
| |
| try { |
| DBInputFormat.DBInputSplit split = getSplit(); |
| if (split.getLength() > 0 && split.getStart() > 0) { |
| String querystring = query.toString(); |
| |
| query = new StringBuilder(); |
| query.append("SELECT * FROM (SELECT a.*,ROWNUM dbif_rno FROM ( "); |
| query.append(querystring); |
| query.append(" ) a WHERE rownum <= ").append(split.getStart()); |
| query.append(" + ").append(split.getLength()); |
| query.append(" ) WHERE dbif_rno >= ").append(split.getStart()); |
| } |
| } catch (IOException ex) { |
| // ignore, will not throw. |
| } |
| |
| return query.toString(); |
| } |
| |
| /** |
| * Set session time zone. |
| * @param conf The current configuration. |
| * We read the 'oracle.sessionTimeZone' property from here. |
| * @param conn The connection to alter the timezone properties of. |
| */ |
| public static void setSessionTimeZone(Configuration conf, |
| Connection conn) throws SQLException { |
| // need to use reflection to call the method setSessionTimeZone on |
| // the OracleConnection class because oracle specific java libraries are |
| // not accessible in this context. |
| Method method; |
| try { |
| method = conn.getClass().getMethod( |
| "setSessionTimeZone", new Class [] {String.class}); |
| } catch (Exception ex) { |
| LOG.error("Could not find method setSessionTimeZone in " |
| + conn.getClass().getName(), ex); |
| // rethrow SQLException |
| throw new SQLException(ex); |
| } |
| |
| // Need to set the time zone in order for Java |
| // to correctly access the column "TIMESTAMP WITH LOCAL TIME ZONE". |
| // We can't easily get the correct Oracle-specific timezone string |
| // from Java; just let the user set the timezone in a property. |
| String clientTimeZone = conf.get(SESSION_TIMEZONE_KEY, "GMT"); |
| try { |
| method.setAccessible(true); |
| method.invoke(conn, clientTimeZone); |
| LOG.info("Time zone has been set to " + clientTimeZone); |
| } catch (Exception ex) { |
| LOG.warn("Time zone " + clientTimeZone |
| + " could not be set on Oracle database."); |
| LOG.warn("Setting default time zone: GMT"); |
| try { |
| // "GMT" timezone is guaranteed to exist. |
| method.invoke(conn, "GMT"); |
| } catch (Exception ex2) { |
| LOG.error("Could not set time zone for oracle connection", ex2); |
| // rethrow SQLException |
| throw new SQLException(ex); |
| } |
| } |
| } |
| } |