1:利用sql自带的存储过程
exec sp_pkeys @table_name='表名'
2:利用系统表information_schema.key_column_usage
select table_name,column_name from information_schema.key_column_usage
where table_name='表名'
3: 以下这个查询表结构的语句可能大家都见过：
利用syscolumns,sysindexes,sysindexkeys三个表关联可以查出主键
select
(case when a.colorder=1 then d.name else '' end) n'表名',
a.colorder n'字段序号',
a.name n'字段名',
(case when columnproperty( a.id,a.name,'isidentity')=1 then '√'else '' end) n'标识',
(case when (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'))>0 then '√' else '' end) n'主键',
b.name n'类型',
a.length n'占用字节数',
columnproperty(a.id,a.name,'precision') as n'长度',
isnull(columnproperty(a.id,a.name,'scale'),0) as n'小数位数',
(case when a.isnullable=1 then '√'else '' end) n'允许空',
isnull(e.text,'') n'默认值',
isnull(g.[value],'') as n'字段说明'
--into ##tx
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 sysproperties g
on a.id=g.id and a.colid = g.smallid
order by object_name(a.id),a.colorder
4:
select o.name as 表名,c.name as 字段名,k.colid as 字段序号,k.keyno as 索引顺序 from sysindexes i
join sysindexkeys k on i.id = k.id and i.indid = k.indid
join sysobjects o on i.id = o.id
join syscolumns c on i.id=c.id and k.colid = c.colid
where o.xtype = 'u'
and exists(select 1 from sysobjects where xtype = 'pk' and name = i.name)
order by o.name,k.colid
