SQL Server 数据库结构查询

SELECT ( case when a . colorder = 1 then d . name else null end ) 表名, a . colorder 字段序号, a . name 字段名,

(case when COLUMNPROPERTY( a.id,a.name,'IsIdentity')=1 then '√'else '' end) 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) 主键,b.name 类型,a.length 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) 允许空,

isnull(e.text,'') 默认值,isnull(g.[value], ' ') AS [说明]

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 sys.extended_properties g on a.id=g.major_id AND a.colid=g.minor_id

left join sys.extended_properties f on d.id=f.class and f.minor_id=0

where b.name is not null

order by a.id,a.colorder

     公司程序员更新好几代，但是数据库结构一直没变，而最初也没有规范的生成数据库字段解释文档，仅仅在程序中有注释。但苦逼测试怎么可能看到程序呢。一个数据库中所有表的结构可以用以上的语句查询，其中说明一栏一般情况下会有该字段的说明。如果是特定查询某个表的结构，可以将倒数第二行改为：

                                                                          WHERE d.name='表名'

    另外以下是一些可能会用到的数据库查询语句

1、查询服务器中所有数据库名称

   
   
     
     
     
     

    
    
      
      
      
      

     
     SELECT Name FROM Master..SysDatabases ORDER BY Name
    
    
      
      
      
      
   
   
     
     
     
     

2、查询某个数据库都有些什么表

select * from 表名.dbo.sysobjects

where xtype='U'

order by name

其中各个xtype的解释如下：


AF = Aggregate function (CLR)                                                C = CHECK constraint
D = Default or DEFAULT constraint                                          F = FOREIGN KEY constraint
L = Log                                                                                      FN = Scalar function
FS = Assembly (CLR) scalar-function                                         FT = Assembly (CLR) table-valued function        
IF = In-lined table-function                                                       IT = Internal table
P = Stored procedure                                                               PC = Assembly (CLR) stored-procedure
PK = PRIMARY KEY constraint (type is K)                                 RF = Replication filter stored procedure
S = System table                                                                       SN = Synonym
SQ = Service queue                                                                   TA = Assembly (CLR) DML trigger
TF = Table function                                                                   TR = SQL DML Trigger
TT = Table type                                                                         U = User table
UQ = UNIQUE constraint (type is K)                                         V = View
X = Extended stored procedure

3、查询某个表的主键

   
   
     
     
     
     

    
    
      
      
      
      

     
     SELECT  name FROM SysColumns 
    
    
      
      
      
      
    
    
      
      
      
      

     
     WHERE id=Object_Id('表名') 
    
    
      
      
      
      
    
    
      
      
      
      

     
     and colid=(select top 1 keyno from sysindexkeys where id=Object_Id('表名'))
    
    
      
      
      
      
   
   
     
     
     
     

4、 查询某个表的数据的长度

   
   
     
     
     
     

    
    
      
      
      
      

     
     select sum(Length) as Length_total from SysColumns
    
    
      
      
      
      
    
    
      
      
      
      

     
     where id=Object_Id('表名')