COBSQ0017 HostVariable is not preceded by a colon.

The SQL Option preprocessor has detected a host variable in an EXEC SQL SET statement that is not preceded by a colon. Although DB2 and XDB Server currently accept host variables without colons, this practice is unconventional and it may not be supported in future releases.

No action is required, as this is a warning. However, you might want to include the colon now to avoid problems in future releases of this software.