IP地址转化为数字，charindex ，SUBSTRING

  SET NOCOUNT ON; 
  declare  @I_PCity table
    (
     IPStart  nvarchar(255), 
      Area   nvarchar(255),
       CityID int,
        IPID  int 
       
    )
      declare @IPStart nvarchar(255),
       @diana int,   --存放点
       @dianb int,
       @dianc int,
       
       @liea bigint,    -- 存放列     
       @lieb  bigint,
       @liec bigint,
       @lied bigint,
       
       @intlon bigint   --存放化为的整数
     insert into  @I_PCity(IPStart, Area, CityID, IPID ) select  IPStart,  Area, CityID, IPID   from I_IPCity (nolock)  where IPID>= 430000   and IPStart is not null and IP3 is null
    -- 
     while( exists(select top 1 * from @I_PCity))
     begin
     
    set @IPStart= (select top 1 IPStart from @I_PCity  );
    set @diana= charindex(‘.‘,@IPStart)       --第一个点的下标
    set @dianb= charindex(‘.‘,@IPStart, @diana +1 )  --第二个点的下标
    set @dianc= charindex(‘.‘,@IPStart, @dianb  +1 )  --第三个点的下标
  
    set @liea  =  SUBSTRING(@IPStart,1,@diana-1)    --第一列的值    
    set @lieb  =SUBSTRING(@IPStart,@diana+1,@dianb-@diana-1 )--第二列的值       
    set @liec  =SUBSTRING(@IPStart,@dianb+1,@dianc-@dianb-1 )--第三列的值
    set @lied  =SUBSTRING(@IPStart,@dianc+1, LEN(@IPStart))--第四列的值
    set @intlon=  @lied+(@liec*1000)+(@lieb*1000000)+(@liea*1000000000)  --拼为整数
        update I_IPCity set IP3 =@intlon   where IPID=  (select top 1 IPID from @I_PCity)
         delete top(1) from @I_PCity
     end

USE [91hurong]
GO
/****** Object:  StoredProcedure [dbo].[ProIP]    Script Date: 08/13/2015 08:40:16 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER PROCEDURE  [dbo].[ProIP]
    -- Add the parameters for the stored procedure here
   @str  varchar(50)
AS
BEGIN
 
    declare @IPStart nvarchar(255), --存放传入的数据
       @diana int,   --存放点
       @dianb int,
       @dianc int,
       
       @liea bigint,    -- 存放列     
       @lieb  bigint,
       @liec bigint,
       @lied bigint,
       
       @intlon bigint   --存放化为的整数
    set @IPStart= @str;               --传入的IP‘1.11.6.6‘
     -- set @IPStart= ‘1.11.6.6‘;  
    set @diana= charindex(‘.‘,@IPStart)       --第一个点的下标
    set @dianb= charindex(‘.‘,@IPStart, @diana +1 )  --第二个点的下标
    set @dianc= charindex(‘.‘,@IPStart, @dianb  +1 )  --第三个点的下标
  
    set @liea  =  SUBSTRING(@IPStart,1,@diana-1)    --第一列的值    
    set @lieb  =SUBSTRING(@IPStart,@diana+1,@dianb-@diana-1 )--第二列的值       
    set @liec  =SUBSTRING(@IPStart,@dianb+1,@dianc-@dianb-1 )--第三列的值
    set @lied  =SUBSTRING(@IPStart,@dianc+1, LEN(@IPStart))--第四列的值
    set @intlon=  @lied+(@liec*1000)+(@lieb*1000000)+(@liea*1000000000)  --拼为整数
      
      declare @inta  bigint
      set @inta=(select top 1  IP3   from I_IPCity  where IP3>@intlon  and IPStart is not null and IPID is not null and IP3 is not null order by IP3 asc)
      select top 1 * from I_IPCity where IP3<@inta and IPStart is not null and IPID is not null and IP3 is not null  order by IP3 desc    --返回‘61.177.117.6‘在表中对应的数据 
END 
exec ProIP ‘61.177.117.6‘

 ‘Arg.ea‘  对应位置

:1 2 3 4 5 6

 charindex(‘.‘,‘Arg.ea‘) >0   --如果大于零，则表示字符串Area中含有字符串CityName； 此例为true

 charindex(‘.‘,‘Arg.ea‘,2 )  -- 从第二个位置后，也就是从 字母‘r‘后开始找，先判断 ‘g’是否为‘.’ ，为否；继续判断‘.’是否为‘.’，此表达式为true

 SUBSTRING(‘Arg.ea‘,1,2)  --截取 字符串 ‘Arg.ea‘中 第一个位置到第二个位置 ；也就是‘Ar’