分类目录归档：SQL Server

两表连接，取出其中某些项不重复的数据

发表于 2010 年 8 月 4 日 由 惜分飞

有省、市数据库表，现在要求只取每一个省中的一个市出来

数据库脚步如下

省表：

CREATE TABLE [dbo].[mem_province](
 [id] [int] NOT NULL,
 1 [nvarchar](6) NOT NULL,
 [name] [nvarchar](40) NULL,
 CONSTRAINT [PK_mem_province] PRIMARY KEY CLUSTERED
(
 1 ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]

市表：

CREATE TABLE [dbo].[mem_city](
 [id] [int] NOT NULL,
 1 [nvarchar](6) NOT NULL,
 [name] [nvarchar](50) NULL,
 [provinceId] [nvarchar](6) NULL,
 CONSTRAINT [PK_mem_city] PRIMARY KEY CLUSTERED
(
 1 ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]

执行sql语句为：


SELECT *
FROM   (
 SELECT a.id aid,
 a.code acode,
 a.name aname,
 b.id bid,
 b.code bcode,
 b.name bname,
 b.provinceId bprovinceId
 FROM   mem_province a left   JOIN
 mem_city b
 on  a.code= b.provinceId
 )c
WHERE  NOT   EXISTS (
 SELECT 1
 FROM   (SELECT a.id aid,
 a.code acode,
 a.name aname,
 b.id bid,
 b.code bcode,
 b.name bname,
 b.provinceId bprovinceId
 FROM   mem_province a LEFT   JOIN
 mem_city b
 on  a.code= b.provinceId)e
 WHERE  e.bid<c.bid
 AND  e.aname = c.aname
) ORDER BY aid

结果如：

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多种方式的md5加密

发表于 2010 年 8 月 1 日 由 惜分飞

一、oracle实现md5加密：

CREATE OR REPLACE function fn_md5(input_string VARCHAR2) return varchar2
IS
raw_input RAW(128) := UTL_RAW.CAST_TO_RAW(input_string);
decrypted_raw RAW(2048);
error_in_input_buffer_length EXCEPTION;
BEGIN
sys.dbms_obfuscation_toolkit.MD5(input => raw_input,checksum => decrypted_raw);
return rawtohex(decrypted_raw);
END;

二、mysql实现md5加密：

select upper(md5('abc')) from cdb_settings limit 1;


注意问题：在mysql中不知道为什么使用了upper不能转化为大写，尝试了几个编码的mysql库都不行，也许是我mysql版本的问题，先记录下mysql版本

三、Sql Server 实现md5加密：

select hashbytes('MD5', 'abc');

四、C#实现md5加密：

string abc=System.Web.Security.FormsAuthentication.
HashPasswordForStoringInConfigFile("abc", "MD5") ;
 Response.Write(abc);

五、Javascript实现md5加密：

var hexcase = 0; function hex_md5(a)
{ return rstr2hex(rstr_md5(str2rstr_utf8(a))) }
function hex_hmac_md5(a, b)
{ return rstr2hex(rstr_hmac_md5(str2rstr_utf8(a), str2rstr_utf8(b))) }
 function md5_vm_test()
{ return hex_md5("abc").toLowerCase() == "900150983cd24fb0d6963f7d28e17f72" }
 function rstr_md5(a)
{ return binl2rstr(binl_md5(rstr2binl(a), a.length * 8)) }
 function rstr_hmac_md5(c, f)
{ var e = rstr2binl(c); if (e.length > 16)
{ e = binl_md5(e, c.length*8) }
 var a = Array(16), d = Array(16);
 for (var b = 0; b < 16; b++)
{ a[b] = e[b] ^ 909522486; d[b] = e[b] ^ 1549556828 }
var g = binl_md5(a.concat(rstr2binl(f)), 512 + f.length * 8);
return binl2rstr(binl_md5(d.concat(g), 512 + 128)) }
function rstr2hex(c) { try { hexcase } catch (g) { hexcase = 0 }
 var f = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
 var b = ""; var a; for (var d = 0; d < c.length; d++) { a = c.charCodeAt(d);
 b += f.charAt((a >>> 4) & 15) + f.charAt(a & 15) } return b } function str2rstr_utf8(c)
 { var b = ""; var d = -1; var a, e; while (++d < c.length)
{ a = c.charCodeAt(d); e = d + 1 < c.length ? c.charCodeAt(d + 1) : 0;
 if (55296 <= a && a <= 56319 && 56320 <= e && e <= 57343)
{ a = 65536 + ((a & 1023) << 10) + (e & 1023); d++ }
if (a <= 127) { b += String.fromCharCode(a) }
else { if (a <= 2047) { b += String.fromCharCode(192 | ((a >>> 6) & 31),
 128 | (a & 63)) } else { if (a <= 65535) { b += String.fromCharCode(224
| ((a >>> 12) & 15), 128 | ((a >>> 6) & 63), 128 | (a & 63)) }
else { if (a <= 2097151) { b += String.fromCharCode(240 |
((a >>> 18) & 7), 128 | ((a >>> 12) & 63), 128 | ((a >>> 6) & 63),
 128 | (a & 63)) } } } } } return b } function rstr2binl(b)
{ var a = Array(b.length >> 2); for (var c = 0; c<a.length; c++)
 { a1 = 0 } for (var c = 0; c <b.length*8;c =c+8 )
{ a1 |= (b.charCodeAt(c / 8 ) & 255) << (c % 32) } return a }
function binl2rstr(b) { var a = ""; for (var c = 0; c<b.length * 32; c=c+8)
 { a += String.fromCharCode((b1 >>> (c % 32)) & 255) }
 return a } function binl_md5(p, k) { p[k >> 5] |= 128 << ((k) % 32);
p[(((k + 64) >>> 9) << 4) + 14] = k; var o = 1732584193;
var n = -271733879; var m = -1732584194; var l = 271733878;
 for (var g = 0; g < p.length; g += 16) { var j = o; var h = n;
var f = m; var e = l; o = md5_ff(o, n, m, l, p[g + 0], 7, -680876936);
 l = md5_ff(l, o, n, m, p[g + 1], 12, -389564586); m = md5_ff(m, l, o, n, p[g + 2], 17, 606105819);
n = md5_ff(n, m, l, o, p[g + 3], 22, -1044525330); o = md5_ff(o, n, m, l, p[g + 4], 7, -176418897);
l = md5_ff(l, o, n, m, p[g + 5], 12, 1200080426); m = md5_ff(m, l, o, n, p[g + 6], 17, -1473231341);
 n = md5_ff(n, m, l, o, p[g + 7], 22, -45705983); o = md5_ff(o, n, m, l, p[g + 8], 7, 1770035416);
l = md5_ff(l, o, n, m, p[g + 9], 12, -1958414417); m = md5_ff(m, l, o, n, p[g + 10], 17, -42063);
 n = md5_ff(n, m, l, o, p[g + 11], 22, -1990404162); o = md5_ff(o, n, m, l, p[g + 12], 7, 1804603682);
 l = md5_ff(l, o, n, m, p[g + 13], 12, -40341101); m = md5_ff(m, l, o, n, p[g + 14], 17, -1502002290);
n = md5_ff(n, m, l, o, p[g + 15], 22, 1236535329); o = md5_gg(o, n, m, l, p[g + 1], 5, -165796510);
 l = md5_gg(l, o, n, m, p[g + 6], 9, -1069501632); m = md5_gg(m, l, o, n, p[g + 11], 14, 643717713);
n = md5_gg(n, m, l, o, p[g + 0], 20, -373897302); o = md5_gg(o, n, m, l, p[g + 5], 5, -701558691);
 l = md5_gg(l, o, n, m, p[g + 10], 9, 38016083); m = md5_gg(m, l, o, n, p[g + 15], 14, -660478335);
n = md5_gg(n, m, l, o, p[g + 4], 20, -405537848); o = md5_gg(o, n, m, l, p[g + 9], 5, 568446438);
l = md5_gg(l, o, n, m, p[g + 14], 9, -1019803690); m = md5_gg(m, l, o, n, p[g + 3], 14, -187363961);
 n = md5_gg(n, m, l, o, p[g + 8], 20, 1163531501); o = md5_gg(o, n, m, l, p[g + 13], 5, -1444681467);
 l = md5_gg(l, o, n, m, p[g + 2], 9, -51403784); m = md5_gg(m, l, o, n, p[g + 7], 14, 1735328473);
n = md5_gg(n, m, l, o, p[g + 12], 20, -1926607734); o = md5_hh(o, n, m, l, p[g + 5], 4, -378558);
l = md5_hh(l, o, n, m, p[g + 8], 11, -2022574463); m = md5_hh(m, l, o, n, p[g + 11], 16, 1839030562);
 n = md5_hh(n, m, l, o, p[g + 14], 23, -35309556); o = md5_hh(o, n, m, l, p[g + 1], 4, -1530992060);
 l = md5_hh(l, o, n, m, p[g + 4], 11, 1272893353); m = md5_hh(m, l, o, n, p[g + 7], 16, -155497632);
n = md5_hh(n, m, l, o, p[g + 10], 23, -1094730640); o = md5_hh(o, n, m, l, p[g + 13], 4, 681279174);
l = md5_hh(l, o, n, m, p[g + 0], 11, -358537222); m = md5_hh(m, l, o, n, p[g + 3], 16, -722521979);
n = md5_hh(n, m, l, o, p[g + 6], 23, 76029189); o = md5_hh(o, n, m, l, p[g + 9], 4, -640364487);
l = md5_hh(l, o, n, m, p[g + 12], 11, -421815835); m = md5_hh(m, l, o, n, p[g + 15], 16, 530742520);
n = md5_hh(n, m, l, o, p[g + 2], 23, -995338651); o = md5_ii(o, n, m, l, p[g + 0], 6, -198630844);
l = md5_ii(l, o, n, m, p[g + 7], 10, 1126891415); m = md5_ii(m, l, o, n, p[g + 14], 15, -1416354905);
n = md5_ii(n, m, l, o, p[g + 5], 21, -57434055); o = md5_ii(o, n, m, l, p[g + 12], 6, 1700485571);
l = md5_ii(l, o, n, m, p[g + 3], 10, -1894986606); m = md5_ii(m, l, o, n, p[g + 10], 15, -1051523);
n = md5_ii(n, m, l, o, p[g + 1], 21, -2054922799); o = md5_ii(o, n, m, l, p[g + 8], 6, 1873313359);
 l = md5_ii(l, o, n, m, p[g + 15], 10, -30611744); m = md5_ii(m, l, o, n, p[g + 6], 15, -1560198380);
n = md5_ii(n, m, l, o, p[g + 13], 21, 1309151649); o = md5_ii(o, n, m, l, p[g + 4], 6, -145523070);
l = md5_ii(l, o, n, m, p[g + 11], 10, -1120210379); m = md5_ii(m, l, o, n, p[g + 2], 15, 718787259);
n = md5_ii(n, m, l, o, p[g + 9], 21, -343485551); o = safe_add(o, j); n = safe_add(n, h);
m = safe_add(m, f); l = safe_add(l, e) } return Array(o, n, m, l) }
function md5_cmn(h, e, d, c, g, f) { return safe_add(bit_rol(safe_add(safe_add(e, h),
safe_add(c, f)), g), d) } function md5_ff(g, f, k, j, e, i, h)
{ return md5_cmn((f & k) | ((~f) & j), g, f, e, i, h) } function md5_gg(g, f, k, j, e, i, h)
{ return md5_cmn((f & j) | (k & (~j)), g, f, e, i, h) } function md5_hh(g, f, k, j, e, i, h)
{ return md5_cmn(f ^ k ^ j, g, f, e, i, h) } function md5_ii(g, f, k, j, e, i, h)
{ return md5_cmn(k ^ (f | (~j)), g, f, e, i, h) } function safe_add(a, d)
{ var c = (a & 65535) + (d & 65535); var b = (a >> 16) + (d >> 16) + (c >> 16);
return (b << 16) | (c & 65535) } function bit_rol(a, b) { return (a << b) | (a >>> (32 - b)) }

实现： 

<script src="md5-min.js" type="text/javascript"></script>
 <script type="text/javascript">
 alert('abc经过md5加密后结果为：\n'+hex_md5('abc'));
 </script>

六、php实现md5加密：

echo strtoupper(md5('abc')) ;

发表在 Asp.Net, JavaScript, MySQL, Oracle, PHP, SQL Server | 一条评论

通过sql server 数据库中的sql语句实现项目需求

发表于 2010 年 6 月 13 日 由 惜分飞

最近都关注oracle，今天没有办法，因为项目使用的是sql server数据库，许多东西都忘记的差不多了。需要实现一个功能，本来可以使用程序去实现，但是我不爽，一定想通过数据库本身来解决这个问题。问题大概是：

项目中是要实现在别人寻找到宝贝后，要回答一个问题，这个问题暂时定为有四个选项，其中一个正确的，在数据库中使用两张表来实现，一张是记录问题的题目和答案（表一），另一张表专门用来记录每个题目中的选项（表二），表的sql脚本如下：

表一：

USE [xb_new]
GO
/****** 对象:  Table [dbo].[Question]    脚本日期: 06/13/2010 21:17:05 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Question](
[id] [int] IDENTITY(1,1) NOT NULL,
[iss_id] [int] NULL,
[answer] [nvarchar](50) NULL,
[question] [nvarchar](150) NULL,
CONSTRAINT [PK_Question_] PRIMARY KEY CLUSTERED
(
[id] ASC
)WITH  (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF,  ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [PRIMARY]

表中数据如下：

表二：

USE [xb_new]
GO
/****** 对象:  Table [dbo].[Qusetion_Answer]    脚本日期: 06/13/2010 21:18:12 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Qusetion_Answer](
[id] [int] IDENTITY(1,1) NOT NULL,
[qid] [int] NOT NULL,
[qtext] [nvarchar](50) NOT NULL,
[qvalue] [nvarchar](2) NULL
) ON [PRIMARY]

表中数据如下


现在需求是：把一个题目的四个选项合并到一起，并为了在网页上换行，显示题目，显示答案。

其中难道是行列转换，以前在orcal中都是使用decode来实现的，现在郁闷的sql server中竟然不支持这个函数，只能我在oracle中比较讨厌的case（主要要多写很多when、then、end我不喜欢，而且还容易忘记格 式）来实现。实现sql脚本如下：

SELECT a,q,aa+'<br>'+bb+'<br>'+cc+'<br>'+dd result FROM
(SELECT DISTINCT answer a,Question.Question q,
aa=MAX(CASE qvalue WHEN 'A' THEN '(A)'+qtext END),
bb=max(CASE qvalue WHEN 'B' THEN '(B)'+qtext END),
cc=max(CASE qvalue WHEN 'C' THEN '(C)'+qtext END),
dd=max(CASE qvalue WHEN 'D' THEN '(D)'+qtext END)
FROM dbo.Question,dbo.Qusetion_Answer
WHERE qid=dbo.Question.id GROUP BY dbo.Question.answer,Question.Question) temp;

结果如下：

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