SQLServer查询一个表的字段定义信息

declare @table_name as varchar(max)
declare @table_id as varchar(max)
set @table_name='sys_user'  -- 把 sys_user 替换为要查询的表名
select @table_id=object_id  from sys.tables where name=@table_name  

select @table_name table_name, a.name column_name, b.name data_type, a.max_length, 
    a.precision, a.is_nullable, c.value description
from sys.columns a join sys.types b on b.user_type_id=a.user_type_id
  left join sys.extended_properties c on  c.major_id=@table_id and c.minor_id=a.column_id
where a.object_id = @table_id  order by a.column_id

测试结果：