經典sql語句

2021-09-05 19:21:57 字數 2431 閱讀 7881

1、獲取表結構,tbl_bas_druginfo為表明

select case isnull(i.name, '')

when '' then ''

else '*'

end as ispk,

object_name(a.id) as t_name,

a.name as c_name,

isnull(substring(m.text, 1, 254), '') as pbc_init,

t.name as f_datatype,

case isnull(typeproperty(t.name, 'scale'), '')

when '' then cast(a.prec as varchar)

else cast(a.prec as varchar) + ',' + cast(a.scale as varchar)

end as f_scale,

a.isnullable as f_isnullable

from syscolumns as a

join systypes as t

on (a.xtype = t.xusertype and a.id = object_id('tbl_bas_druginfo') )

left join ( sysindexes as i

join syscolumns as a1

on ( i.id = a1.id and a1.id = object_id('tbl_bas_druginfo') and (i.status & 0x800) = 0x800 and a1.colid <= i.keycnt) )

on ( a.id = i.id and a.name = index_col('tbl_bas_druginfo', i.indid, a1.colid) )

left join syscomments as m

on ( m.id = a.cdefault and objectproperty(a.cdefault, 'isconstraint') = 1 )

order by a.colid asc

提取資料庫內所有表的字段詳細說明的sql語句

select

(case when a.colorder=1 then d.name else '' end) n'表名',

a.colorder n'字段序號',

a.name n'欄位名',

(case when columnproperty( a.id,a.name,'isidentity')=1 then '√'else ''

end) n'標識',

(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'主鍵',

b.name n'型別',

a.length n'占用位元組數',

columnproperty(a.id,a.name,'precision') as n'長度',

isnull(columnproperty(a.id,a.name,'scale'),0) as n'小數字數',

(case when a.isnullable=1 then '√'else '' end) n'允許空',

isnull(e.text,'') n'預設值',

isnull(g.[value],'') as n'字段說明'

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

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