根据表明获取字段及对应说明

SELECT
   TableName = OBJECT_NAME(c.object_id),
   ColumnsName = c.name,
   Description = ex.value,
   ColumnType=t.name,
   Length=c.max_length
   FROM
   sys.columns c
   LEFT OUTER JOIN
   sys.extended_properties ex
   ON
   ex.major_id = c.object_id
   AND ex.minor_id = c.column_id
   AND ex.name = 'MS_Description'
   left outer join
   systypes t
   on c.system_type_id=t.xtype
   WHERE
   OBJECTPROPERTY(c.object_id, 'IsMsShipped')=0
   AND OBJECT_NAME(c.object_id) ='tablename' 

1.获取所有数据库名:
Select Name FROM Master..SysDatabases orDER BY Name
2.获取所有表名:
Select Name FROM DatabaseName..SysObjects Where XType='U' orDER BY Name
XType='U':表示所有用户表;
XType='S':表示所有系统表;
3.获取所有字段名:
Select Name FROM SysColumns Where id=Object_Id('TableName')