MSSQL 获取数据库字段类型

 SELECT
    col.name AS 列名,
    typ.name as 数据类型,
    col.max_length AS 占用字节数,
    col.precision AS 数字长度,
    col.scale AS 小数位数,
    col.is_nullable  AS 是否允许非空,
    col.is_identity  AS 是否自增,
    case when exists
       ( SELECT 1
         FROM
           sys.indexes idx
             join sys.index_columns idxCol
             on (idx.object_id = idxCol.object_id)
          WHERE
             idx.object_id = col.object_id
             AND idxCol.index_column_id = col.column_id
             AND idx.is_primary_key = 1
        ) THEN 1 ELSE 0 END  AS 是否是主键,
   isnull(prop.[value],'-') AS 说明
 FROM
   sys.columns col
     left join sys.types typ
       on (col.system_type_id = typ.system_type_id)
     left join sys.extended_properties prop
       on (col.object_id = prop.major_id AND prop.minor_id = col.column_id)
 WHERE
   col.object_id =
     (SELECT object_id FROM sys.tables WHERE name = 'band')