----更新外部数据模型描述字段的长度为255
----对应的数据表更新见ExtDataModelUpdateFieldLengthUpgradeService
UPDATE t_fah_ext_modflds SET fproperties_tag ='[{"name":"maxLength","class":"java.lang.Integer","val":"255","desc":"字段长度"}]' WHERE fnumber = 'description';
