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https://issues.apache.org/jira/browse/SQOOP-429?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13204613#comment-13204613
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Lars Francke commented on SQOOP-429:
------------------------------------

This is harder than I had hoped because the ORM generation is _everywhere_. 
I've not yet managed to skip the code generation and still get a job running.

But your hunch about the test was correct:
{quote}
Case sensitivity rules for identifiers can be described simply as follows:
* all parts of SQL statements are converted to upper case before processing, 
except identifiers in double quotes and strings in single quotes
* identifiers, both unquoted and double quoted, are then treated as 
case-sensitive
* most database engines follow the same rule, except MySQL, and in some 
respects, MS SQLServer.
{quote}
http://hsqldb.org/doc/2.0/guide/databaseobjects-chapt.html#dbc_common_elements

Which means - if that comment is correct - that this problem might only affect 
MySQL and "in some respects, MS SQLServer".

Unfortunately to expose that problem in a test we'd need to quote column names 
_everywhere_ where they might be included in a query.

One example {{DataDrivenDBRecordReader#getSelectQuery}}:
{code}
query.append('"');
query.append(fieldNames[i]);
query.append('"');
{code}

I've not yet given up but I might have to at some point.
                
> Avro support doesn't take Java reserved words into account
> ----------------------------------------------------------
>
>                 Key: SQOOP-429
>                 URL: https://issues.apache.org/jira/browse/SQOOP-429
>             Project: Sqoop
>          Issue Type: Bug
>    Affects Versions: 1.4.0-incubating
>            Reporter: Lars Francke
>         Attachments: SQOOP-429.patch
>
>
> We have a table with a column named {{class}} which Sqoops renames to 
> {{_class}} internally. That's working great until it comes to the Avro 
> support.
> The generated Avro schema has a field called {{class}} as well but in 
> {{AvroImportMapper#toGenericRecord}} the {{SqoopRecord#getFieldMap}} method 
> is called which returns the changed column name. This leads to a 
> {{NullPointerException}} in {{GenericData$Record#put}} because it tries to 
> find the wrong field. 
> I'm far from understanding Sqoops internals but it seems like there are two 
> solutions: Either change the generated Avro Schema (which would probably be 
> an easy but annoying fix) or somehow check if a field from the SqoopRecord 
> was renamed due to a reserved word and then rename it back here. I'd love to 
> provide a patch for this as we need this to work but I don't know which way's 
> preferred and I would need to do a bit of digging.
> {code}
> java.lang.NullPointerException
>       at org.apache.avro.generic.GenericData$Record.put(GenericData.java:58)
>       at 
> org.apache.sqoop.mapreduce.AvroImportMapper.toGenericRecord(AvroImportMapper.java:68)
>       at 
> org.apache.sqoop.mapreduce.AvroImportMapper.map(AvroImportMapper.java:59)
>       at 
> org.apache.sqoop.mapreduce.AvroImportMapper.map(AvroImportMapper.java:43)
>       at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144)
>       at 
> org.apache.sqoop.mapreduce.AutoProgressMapper.run(AutoProgressMapper.java:183)
>       at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:647)
>       at org.apache.hadoop.mapred.MapTask.run(MapTask.java:323)
>       at org.apache.hadoop.mapred.Child$4.run(Child.java:270)
>       at java.security.AccessController.doPrivileged(Native Method)
>       at javax.security.auth.Subject.doAs(Subject.java:396)
>       at 
> org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1127)
>       at org.apache.hadoop.mapred.Child.main(Child.java:264)
> {code}

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