To meet the SQL requirements of some relational database management systems (RDBMSs), the Database Connectors run time truncates long field names to the maximum allowed by the RDBMS. (In the case of the OCCURS clause described above, the truncation is to the original name, not the appended index numbers. However, the final name, including the index number, is limited to the RDBMS maximum.) It's a good idea to make sure that your field names are unique (and meaningful) within the first 18 characters.
The database you are connecting to may allow longer names, and if so, more characters are used. Names longer than 30 characters generate a warning. Instead of allowing default truncation, use the NAME XFD directive to give a shorter alias to a field with a long name. Note that within the COBOL application you can continue to use the original name. The NAME XFD directive affects only the XFD connection to the RDBMS table.