The document was fixed a few releases ago. The output field type is controlled by all field values, not just the first 8.
解决办法
Convert the field to a new field type in ArcMap after importing by using the Calculate Field tool.This knowledgebase article states it is only for older versions of ArcMap but works in newer versions as well:Article # 34315: Change the data type for an existing field<a href="http://support.esri.com/em/knowledgebase/techarticles/detail/34315" target="_blank">http://support.esri.com/em/knowledgebase/techarticles/detail/34315</a>