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