sqoop从DB2迁移数据到HDFS

Sqoop import job failed to read data from DB2 database which has UTF8 encoding. Essentially, even the data cannot be read at DB2 with select queries as there are some characters which are not in UTF8.

Sqoop job will throw an error similar to below:

Error: java.io.IOException: SQLException in nextKeyValue
        at org.apache.sqoop.mapreduce.db.DBRecordReader.nextKeyValue(DBRecordReader.java:265)
..
..
Caused by: com.ibm.db2.jcc.am.SqlException: [jcc][t4][1065][12306][4.19.26] Caught java.io.CharConversionException.  See attached Throwable for details. ERRORCODE=-4220, SQLSTATE=null
        at com.ibm.db2.jcc.am.kd.a(Unknown Source)
        at com.ibm.db2.jcc.am.kd.a(Unknown Source)
..
..
Caused by: java.nio.charset.MalformedInputException: Input length = 527
        at com.ibm.db2.jcc.am.s.a(Unknown Source)
        ... 22 more
Caused by: sun.io.MalformedInputException
        at sun.io.ByteToCharUTF8.convert(ByteToCharUTF8.java:105)
        ... 23 more

2018-09-10 06:01:34,879 INFO mapreduce.Job:  map 0% reduce 0%

2018-09-10 06:01:45,942 INFO mapreduce.Job:  map 100% reduce 0%

2018-09-10 06:02:02,039 INFO mapreduce.Job: Task Id : attempt_1535965915754_0038_m_000000_2, Status : FAILED

Error: java.io.IOException: SQLException in nextKeyValue

        at org.apache.sqoop.mapreduce.db.DBRecordReader.nextKeyValue(DBRecordReader.java:277)

        at org.apache.hadoop.mapred.MapTask$NewTrackingRecordReader.nextKeyValue(MapTask.java:556)

        at org.apache.hadoop.mapreduce.task.MapContextImpl.nextKeyValue(MapContextImpl.java:80)

        at org.apache.hadoop.mapreduce.lib.map.WrappedMapper$Context.nextKeyValue(WrappedMapper.java:91)

        at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:145)

        at org.apache.sqoop.mapreduce.AutoProgressMapper.run(AutoProgressMapper.java:64)

        at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)

        at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)

        at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)

        at java.security.AccessController.doPrivileged(Native Method)

        at javax.security.auth.Subject.doAs(Subject.java:415)

        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1988)

        at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)

Caused by: com.ibm.db2.jcc.am.SqlException: [jcc][t4][1065][12306][4.16.53] Caught java.io.CharConversionException.  See attached Throwable for details. ERRORCODE=-4220, SQLSTATE=null

        at com.ibm.db2.jcc.am.fd.a(fd.java:723)

        at com.ibm.db2.jcc.am.fd.a(fd.java:60)

        at com.ibm.db2.jcc.am.fd.a(fd.java:112)

        at com.ibm.db2.jcc.am.jc.a(jc.java:2870)

        at com.ibm.db2.jcc.am.jc.p(jc.java:527)

        at com.ibm.db2.jcc.am.jc.N(jc.java:1563)

        at com.ibm.db2.jcc.am.ResultSet.getStringX(ResultSet.java:1153)

        at com.ibm.db2.jcc.am.ResultSet.getString(ResultSet.java:1128)

        at org.apache.sqoop.lib.JdbcWritableBridge.readString(JdbcWritableBridge.java:71)

        at com.cloudera.sqoop.lib.JdbcWritableBridge.readString(JdbcWritableBridge.java:61)

        at PC_KPI_PC_INCIDENT_CFIUS_CONSTRAINED.readFields(PC_KPI_PC_INCIDENT_CFIUS_CONSTRAINED.java:197)

        at org.apache.sqoop.mapreduce.db.DBRecordReader.nextKeyValue(DBRecordReader.java:244)

        ... 12 more

Caused by: java.nio.charset.MalformedInputException: Input length = 574820

        at com.ibm.db2.jcc.am.r.a(r.java:19)

        at com.ibm.db2.jcc.am.jc.a(jc.java:2862)

        ... 20 more

Caused by: sun.io.MalformedInputException

        at sun.io.ByteToCharUTF8.convert(ByteToCharUTF8.java:167)

        at com.ibm.db2.jcc.am.r.a(r.java:16)

        ... 21 more

解决办法：

需要在yarn的mapred-site.xml文件中添加如下配置：

<property>
<name>mapreduce.map.java.opts</name>
<value>-Xmx1024m -Ddb2.jcc.charsetDecoderEncoder=3</value>
</property>

http://www-01.ibm.com/support/docview.wss?uid=swg21684365