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sql百万级数据量分页代码,数据类型

2020年3月10日 - 数据网络

高效分页方法代码(sql百万级数据量分页代码)

综合网络资料整理]

@querystr nvarchar(300),–表名、视图名、查询语句@pagesize
int=10,–每页的大小(行数)@pagecurrent int=1,–要显示的页@fdshow nvarchar
(100)=”,–要显示的字段列表,如果查询结果有标识字段,需要指

1.获取所有数据库名:
   (1)、Select Name FROM
Master..SysDatabases order by Name
2.**获取所有表名:

定此值,且不包含标识字段@fdorder nvarchar
(100)=”,–排序字段列表@wherestr nvarchar (200)=”, –内容是’ id=3 and
model_no like ‘%24%’

**   (1)、Select Name FROM SysObjects Where
XType=’U’ orDER BY Name
           XType=’U’:表示所有用户表;
           XType=’S’:表示所有系统表;

and ‘@rscount int=0 output asset @fdshow=’ ‘+@fdshow+’ ‘set @fdorder= ‘
‘+@fdorder+’ ‘set @wherestr= ‘ ‘+@wherestr+’ ‘

   (2)、SELECT name FROM sysobjects WHERE type = ‘U’ AND sysstat =
’83’

declare @fdname nvarchar(250)–表中的主键或表、临时表中的标识列名,@id1
varchar(20),@id2 varchar(20)–开始和结束的记录号,@obj_id int
–对象id,@temp nvarchar(300) –临时语句,@strparam nvarchar(100)
–临时参数

           注意:一般情况只需要type =
‘U’,但有时候会有系统表混在其中(不知道什么原因),加上后面一句后就能删除这些系统表了

declare @strfd nvarchar(2000)–复合主键列表,@strjoin
nvarchar(4000)–连接字段,@strwhere
nvarchar(2000)–查询条件–检查输入参数set
@querystr=ltrim(rtrim(@querystr))select
@obj_id=object_id(@querystr),@fdshow=case isnull(@fdshow,”) when ”
then ‘ *’ else ‘ ‘+@fdshow end,@fdorder=case isnull(@fdorder,”) when
” then ” else ‘ order by

3.**获取所有字段名:**
(1)、Select Name FROM SysColumns Where
id=Object_Id(‘TableName’)

‘+@fdorder end,@querystr=case when @obj_id is not null then ‘
‘+@querystr else ‘

(2)、SELECT syscolumns.name,systypes.name,syscolumns.isnullable,syscolumns.length
FROM syscolumns, systypes WHERE syscolumns.xusertype =
systypes.xusertype AND “syscolumns.id =
object_id(‘tableName’)

(‘+@querystr+’) a’ end–输出总记录数set @temp= ‘select
@rscount=count(*) from ‘ + @querystr+’ ‘+@wherestrset @strparam =
n’@rscount int out’execute sp_executesql @temp,@strparam,@rscount
out–如果显示第一页,可以直接用top来完成if @pagecurrent=1beginselect
@id1=cast(@pagesize as varchar(20))exec(‘select top ‘+@id1+@fdshow+’
from
‘+@querystr+@wherestr+@fdorder)returnend–如果是表,则检查表中是否有标识更或主键if
@obj_id is not null and objectproperty(@obj_id,’istable’)=1beginselect
@id1=cast(@pagesize as
varchar(20)),@id2=cast((@pagecurrent-1)*@pagesize as varchar(20))select
@fdname=name from syscolumns where id=@obj_id and status=0x80if
@@rowcount=0–如果表中无标识列,则检查表中是否有主键beginif not
exists(select 1 from sysobjects where parent_obj=@obj_id and

       注意点:
     (a)这里为了重点突出某些重要内容,选取了其中几项信息输出。
     (b)syscolumns表中只含有数据类型编号,要获取完整的名字需要从systypes表中找,一般用户使用的数据类型用xusertype对应比较好,不会出现一对多的情况。
     (c)syscolumns.length得到的是物理内存的长度,所以nvarchar和varchar等类型在数据库中的显示是这个的一半。

xtype=’pk’)goto lbusetemp–如果表中无主键,则用临时表处理select
@fdname=name from syscolumns where id=@obj_id and colid in(select colid
from sysindexkeys where @obj_id=id and indid in(select indid from
sysindexes where @obj_id=id and name in(select name from sysobjects
where xtype=’pk’ and parent_obj=@obj_id)))

 

if @@rowcount1–检查表中的主键是否为复合主键beginselect
@strfd=”,@strjoin=”,@strwhere=”select
@strfd=@strfd+’,[‘+name+’]’,@strjoin=@strjoin+’ and
a.[‘+name+’]=b.[‘+name+’]’,@strwhere=@strwhere+’ and b.[‘+name+’]
is null’from syscolumns where id=@obj_id and colid in(select colid from
sysindexkeys where @obj_id=id and indid in(select indid from sysindexes
where @obj_id=id and name in(select name from sysobjects where
xtype=’pk’ and parent_obj=@obj_id)))select
@strfd=substring(@strfd,2,2000),@strjoin=substring(@strjoin,5,4000),@strwhere=substring(@strwhere,5,4000)goto
lbusepkendendendelsegoto
lbusetemp/*–使用标识列或主键为单一字段的处理方法–*/lbuseidentity: if
len(@wherestr)10beginexec(‘select top ‘+@id1+@fdshow+’ from
‘+@querystr+@wherestr+’ and ‘+@fdname+’ not in(select top ‘+@id2+’
‘+@fdname+’ from
‘+@querystr+@wherestr+@fdorder+’)’+@fdorder)returnendelsebeginexec(‘select
top ‘+@id1+@fdshow+’ from ‘+@querystr+’ where ‘+@fdname+’ not in(select
top ‘+@id2+’ ‘+@fdname+’ from
‘+@querystr+@fdorder+’)’+@fdorder)returnend/*–表中有复合主键的处理方法–*/lbusepk:exec(‘select
‘+@fdshow+’ from(select top ‘+@id1+’ a.* from(select top 100 percent *
from ‘+@querystr+@fdorder+’) aleft join (select top ‘+@id2+’ ‘+@strfd+’
from ‘+@querystr+@fdorder+’) b on ‘+@strjoin+’where ‘+@strwhere+’)
a’)return/*–用临时表处理的方法–*/lbusetemp:select
@fdname='[id_’+cast(newid() as
varchar(40))+’]’,@id1=cast(@pagesize*(@pagecurrent-1) as
varchar(20)),@id2=cast(@pagesize*@pagecurrent-1 as
varchar(20))exec(‘select ‘+@fdname+’=identity(int,0,1),’+@fdshow+’into
#tb from’+@querystr+@fdorder+’select ‘+@fdshow+’ from #tb where
‘+@fdname+’ between ‘+@id1+’ and ‘+@id2)

4、得到表中主键所包含的列名:

    SELECT syscolumns.name FROM
syscolumns,sysobjects,sysindexes,sysindexkeys WHERE syscolumns.id =
object_id(‘tablename’) AND sysobjects.xtype = ‘PK’ AND
sysobjects.parent_obj = syscolumns.id AND sysindexes.id = syscolumns.id
AND sysobjects.name = sysindexes.name AND sysindexkeys.id =
syscolumns.id AND sysindexkeys.indid = sysindexes.indid AND
syscolumns.colid = sysindexkeys.colid

注意:这是在4张系统表中寻找的,关系比较复杂,大致可以表示为:
syscolumns中存有表中的列信息和表id,sysobjects表中存有主键名字(即PK_Table类似)和表id,sysindexes中存
有主键名字和表id和index编号,sysindexkeys中存有表id和index编号和列编号,一项一项对应起来后就能找到列名了。

 

另外的SQL代码

select syscolumns.name,
systypes.name,
syscolumns.length from syscolumns   

  left join
systypes on syscolumns. xusertype
=systypes. xusertype
 

  where id=(select
id from sysobjects where name=’订货主档’);

go;

或者用这样的写法,执行结果一样:

select syscolumns.name,
systypes.name,
syscolumns.length from syscolumns,systypes

where (syscolumns.id=object_id(‘订货主档’) and syscolumns.xusertype=systypes.xusertype)

order
by syscolumns.colorder;

go

执行结果:(字段只出现一次,正常)

订单号码   
int4

客户编号   
nvarchar    10

员工编号   
int4

订单日期   
datetime    8

要货日期   
datetime    8

送货日期   
datetime    8

送货方式   
int4

运费    money  
8

收货人  nvarchar   
80

送货地址   
nvarchar    120

送货城市   
nvarchar    30

送货行政区 
nvarchar    30

送货邮政编码   
nvarchar    20

送货国家地区   
nvarchar    30

 

 

select syscolumns.name,
systypes.name,
syscolumns.length from syscolumns   

  left join
systypes on syscolumns.xtype=systypes.xtype 

  where id=(select
id from sysobjects where name=’订货主档’);

go;

执行结果:(部分字段出现两次,数据类型不同)

订单号码   
int4

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