表定义如下： postgres=# \d+ uppertest Table "public.uppertest" Column | Type | Collation | Nullable | Default | Storage | Stats target | Description --------+---------+-----------+----------+---------+---------+--------------+------------- UU | integer | | | | plain | | 使用insert into uppertest(UU) values(1); 插入数据是否成功？B A 正确 B 错误