You
need to make sure that DB2® uses
the correct code page (which is identified by a CCSID) to interpret
your data. Otherwise, DB2 might
store or use incorrect data. This situation is most likely to occur
when characters are converted or transferred between systems.
Procedure
To ensure that DB2 interprets
characters correctly:
- Determine the CCSID
of your data sources.
- Based
on the CCSIDs of your data sources, specify the correct CCSIDs for your
subsystem, objects, and applications in DB2. If
the CCSIDs of all of your data sources do not match and you need help
determining the appropriate CCSIDs to specify, call IBM® Software Support.
Recommendation: If possible,
set up your system, applications, and objects to avoid character conversion
on z/OS®,
because character conversion has an expensive CPU cost. You can avoid
character conversion by using the same CCSID in all of your data sources.
Of course, do not do so at the expense of data integrity.
- Set up z/OS Unicode Services.
- Optional: Define any additional character
conversions.
Character conversions are already
defined in the following two places:
- The DB2 catalog table SYSIBM.SYSSTRINGS
- This table contains character conversion definitions from IBM. You might have also added your
own.
- The conversion image in z/OS Unicode Services
- You configured this image when you set up z/OS Unicode Services.
However,
you might need to define additional conversions. If you are not sure
if a particular character conversion is defined to DB2, check your character conversion
definitions.
What to do next
Recommendation: If your DB2 subsystem has users that use
different CCSIDs, be careful when you create and name objects. Choose
identifiers, such as table names and column names, that can be represented
on all clients that access the DB2 subsystem.