JR46434: DATA CAN BE BEING CORRUPTED WHEN MOVED BETWEEN DIFFERENT DATA TYPES WITHOUT ISSUING A WARNING JUSTIFICATION

IBM InfoSphere Information Server, Version 9.1.2

APAR status

• Closed as program error.

Error description

• Data is being corrupted when moved between different data types
  without issuing a warning Justification
  A customer has no way to know when DS is corrupting data today
  in these situations.
  We need to more proactively allow them to handle this scenario.
  

Local fix

• No workaround is suggested
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Transformer, Lookup, or Slowly Changing Dimension stages in
  Parallel jobs where data may be assigned to an output data field
  that cannot contain it.
  ****************************************************************
  PROBLEM DESCRIPTION:
  In a Transformer, Lookup, or Slowly Changing Dimension stage of
  a Parallel job, input data may be assigned to an output data
  field that cannot contain it.
  For example, a field of type Integer may be derived from a
  BigInt.
  There are also cases where an arithmetic expression involving
  non-numeric fields uses an intermediate variable to do
  string-to-number and number-to-string conversion, leading to
  loss of precision owing to the data type used for the
  intermediate variable.
  
  At run time, data that would overflow the output field is
  truncated or
  modified to fit, without a warning being logged by the Transform
  operator.
  So for example an integer that is too large for the destination
  may become negative.
  ****************************************************************
  RECOMMENDATION:
  Apply the patch for JR46434.
  Refer to TechNote:
  http://www.ibm.com/support/docview.wss?uid=swg21639629
  ****************************************************************
  

Problem conclusion

• This change addresses the issue where implicit type conversion
  might lead to data loss, but no warnings are issued to warn a
  user that this may occur.
  
  The function of the change is to:
   - Generate compile-time warnings for potential data loss caused
  by implicit type conversions that are detected in expression.
   - Log a message at job runtime if such warnings have been
  generated, including the message contents.
   - Provide an option to disable the generation of warnings at
  compile time and logging these at run time.
  
  The change will cause a warning file to be written a job?s
  RT_SCnn folder if certain type conversion issues are detected in
  the Transformer, Lookup or Slowly Changing Dimension stages.
  This will only happen if the environment variable
  APT_TRANSFORM_RANGE_CHECK is set to 1 at compile time. Setting
  APT_TRANSFORM_RANGE_CHECK=0, or not defining that variable at
  all, means the warning files are not produced.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Modules/Macros

• CLIENT   SERVER
  

Fix information

• Fixed component name

  WIS DATASTAGE

• Fixed component ID

  5724Q36DS

Applicable component levels

• R850 PSY

     UP

• R870 PSY

     UP

• R910 PSY

     UP