笔记32 SQL2005 查询表结构

笔记32 SQL2005 查询表结构

--SQL2005 查询表结构 
SELECT   
(case when a.colorder=1 then d.name else '' end) as 表名,--如果表名相同就返回空   syscolumns(表字段信息表) a  sysobjects d
     a.colorder as 字段序号,  
     a.name as 字段名,  
     (case when COLUMNPROPERTY( a.id,a.name, 'IsIdentity' )=1 then '√' else '' end) as 标识,   --返回IsIdentity的值，IsIdentity只有两个值：0、1
     (case when (SELECT count(*) FROM sysobjects--查询主键  
                     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' ))>0 then '√' else '' end) as 主键,--查询主键END  
b.name as 类型,   --systypes b
a.length as 占用字节数,  
COLUMNPROPERTY(a.id,a.name,'PRECISION' ) as    长度,  
isnull(COLUMNPROPERTY(a.id,a.name,'Scale' ),0) as 小数位数,  
(case when a.isnullable=1 then '√' else '' end) as 允许空,  
isnull(e.text,'' ) as 默认值,   --syscomments e
isnull(g.[value],'' ) AS 字段说明    --sys.extended_properties g (字段信息表)
FROM syscolumns a left join systypes b   
on a.xtype=b.xusertype  
inner join sysobjects d   
on a.id=d.id and d.xtype='U' and d.name<> 'dtproperties'   
left join syscomments e  
on a.cdefault=e.id  
left join sys.extended_properties g  
on a.id=g.major_id AND a.colid = g.minor_id   
     where d.name='systempara' --所要查询的表  
order by a.id,a.colorder  

/*
select * from sys.extended_properties--字段信息表  
select * from syscolumns--表字段信息表  
select * from sysobjects where sysobjects.type='u' --数据库所有的用户创建的表的信息  
select * from sysobjects where sysobjects.type='s' --数据库所有的系统表的信息  
select * from syscomments --所有的触发器的东西  
--COLUMNPROPERTY 返回有关列或过程参数的信息
*/