|
字段有值的情况下，修改字段的类型，比如id为number类型修改为varchar2
alter table xyj_province_city_area rename column id to city_id;
alter table xyj_province_city_area add id varchar2(40);
update xyj_province_city_area set id=trim(city_id);
alter table xyj_province_city_area drop column city_id; | 
转播
