``++CAST(... AS CHAR/VARCHAR)++`` can be a source of incompatibilities between database versions: the behavior of ``++CAST++`` may not be the same depending on the version of the database system. Such incompatibilities can cause unexpected output from applications that ``++CAST++`` decimal data to ``++CHAR++`` or ``++VARCHAR++``, it's therefore best to avoid using ``++CAST(... AS CHAR/VARCHAR)++``.
* http://www.ibm.com/support/knowledgecenter/SSEPEK_10.0.0/apsg/src/tpc/db2z_relincompatapplsqlfromv9.html[IBM note on SQL release incompatibilities] (see section _Changes to string formatting of decimal data_)