String_truncation
SET STRING_TRUNCATION IGNORE|FAIL|WARN statement is used to change the current
error handling setting (see
Specify Error Handling for String Truncation) for string truncation.
The default setting of silent truncation (IGNORE) may not be suitable in all cases. For example, you may want to be notified when truncation occurs when unloading or reloading a database using unloaddb or copydb, especially if you are migrating to UTF8 using the -nvarchar flag.
In such cases, you can issue:
SET STRING_TRUNCATION WARN