The number of characters or bytes Database Engine 20 exports can exceed or be less than the number of characters or bytes the client application expects to receive unless the export width is set properly.
The export width defines how the system reserves space for each character field in result set rows returned to Teradata clients. The global export width is set by default, but you can change the setting. In addition, users with the required privileges can override the global setting with a session-level export width setting.
64000 bytes is the maximum possible for an exported character string.