获取表SQLSERVER 的表结构信息字段名，长度，精度，类型，NULL,ID,PRI

select sys.columns.name,sys.types.name,sys.columns.precision,sys.columns.scale,sys.columns.is_nullable,(select count(*) from sys.identity_columns where sys.identity_columns.object_id = sys.columns.object_id and sys.columns.column_id = sys.identity_columns.column_id) as is_identity,(select value from sys.extended_properties where sys.extended_properties.major_id = sys.columns.object_id and sys.extended_properties.minor_id = sys.columns.column_id) as description,( SELECT count(*) FROM sysobjects  
WHERE (name in (SELECT name FROM sysindexes  
WHERE (id = a.id) AND (indid in  
(SELECT indid FROM sysindexkeys  
WHERE (id = a.id) AND (colid in  
(SELECT colid FROM syscolumns WHERE (id = a.id) AND (name = a.name)))))))  
AND (xtype = 'PK') ) as is_key 
  from sys.columns,sys.tables,sys.types,syscolumns a 
  where 
  sys.columns.object_id = sys.tables.object_id and 
  sys.columns.system_type_id=sys.types.system_type_id and 
  a.id = sys.tables.object_id  and a.id = sys.columns.object_id and a.name = sys.columns.name and 
  sys.tables.name='yk_typk' 
  order by sys.columns.column_id

YPCD	numeric	4	0	0	0	NULL	1
CDMC	varchar	0	0	1	0	NULL	0
PYDM	varchar	0	0	1	0	NULL	0
CDQC	varchar	0	0	1	0	NULL	0