weidagang2046 2006-12-08 22:01 发表评论
]]>关于索引Q推荐{载的q篇文章
http://blog.csdn.net/dutguoyi/archive/2006/01/10/575617.aspx
改善SQL语句的效?br />http://community.csdn.net/Expert/topic/5087/5087396.xml?temp=.345669
数据量很大怎样加快索检速度
http://community.csdn.net/Expert/topic/5058/5058320.xml?temp=.1229517
索引建立Ҏ(gu)的区?br />http://community.csdn.net/Expert/topic/5068/5068154.xml?temp=.3010218
频繁插入删除数据需要更新烦(ch)?br />http://community.csdn.net/Expert/topic/4937/4937910.xml?temp=.8428614
试?jin)一下sql server 2005 全文(g)?br />http://community.csdn.net/Expert/topic/4878/4878430.xml?temp=.6049311
其他关于效率的高频问?/p>
判断一个表的数据不在另一个表中最优秀Ҏ(gu)Q?br />http://community.csdn.net/Expert/topic/5038/5038742.xml?temp=.4704553
删除千万U表中重复记录的办法
http://community.csdn.net/Expert/topic/5089/5089261.xml?temp=.7907068
数据库数据查询变得不正常cd问题
大数据量Q稳定运行一D|候以后无法得到查询结果?br />http://community.csdn.net/Expert/topic/4810/4810464.xml?temp=9.014529E-02
from: http://m.tkk7.com/zqli/archive/2006/12/08/86391.html
weidagang2046 2006-12-08 21:55 发表评论
]]> CREATE TABLE person (
id SERIAL,
name TEXT
);
?x)自动{换ؓ(f)以下SQL语句Q?
CREATE SEQUENCE person_id_seq;
CREATE TABLE person (
id INT4 NOT NULL DEFAULT nextval('person_id_seq'),
name TEXT
);
from: http://www.pgsqldb.org/twiki/bin/view/PgSQL/PostgreFAQ#4.11.1
weidagang2046 2006-11-26 17:06 发表评论
]]>if p>1 then 'p为PAGE|
if n="next" then'下一?br />sql="select top 26 * from song1 where id > "&pk&" and contains(songtitle,'"&songname&"')" 'PK为当前页的最大ID?br />elseif n="prev" then'上一?br />sql="select top 26 * from song1 where id < "&previd&" and contains(songtitle,'"&songname&"') order by id desc"'previd最ID
end if
else
sql="select top 26 * from song1 where contains(songtitle,'"&songname&"')"'没有指定PAGE?默认W一?br />end if
q里用到?jin)全文检?速度也是很快?我在52万记录下试,最快可?6MS(机器C1.7. DDR 256M),感觉比较可以,我用like代码模糊查询|试过,在结果集很多的情况下比全文更?但是如果l果很少(整个表只有那么几?是漫长的过E?因ؓ(f)要对全表q行扫描!
按上面的Ҏ(gu)不能得出所查询l果得总记录数,q里我们可以用select count(*) 来获取记录L,速度还q得?不过感觉要慢一?特别是记录集很多得情?不过q样占用得内存很得.
以上是我最q搞SQL查询得心(j)?
from: http://www.fixdown.com/article/article/2121.htm
weidagang2046 2006-10-27 12:17 发表评论
]]>①ؓ(f)什么要使用存储q程?
因ؓ(f)它比SQL语句执行?
②存储过E是什?
把一堆SQL语句|在一?q可以根据条件执行不同SQL语句.(AX写作本文时观?
③来一个最单的存储q程
CREATE PROCEDURE dbo.testProcedure_AX
AS
select userID from USERS order by userid desc
?dbo.testProcedure_AX是你创徏的存储过E名,可以改ؓ(f):AXzhz{?别跟关键字冲H就行了(jin).AS下面是一条SQL语句,不会(x)写SQL语句的请回避.
④我怎么在ASP.NET中调用这个存储过E?
下面黄底的这两行够使了(jin).
(tng) (tng) (tng) (tng) (tng) (tng) (tng) public static string GetCustomerCName(ref ArrayList arrayCName,ref ArrayList arrayID)
(tng) (tng) (tng) (tng) (tng) (tng) (tng) {
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) SqlConnection con=ADConnection.createConnection();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) SqlCommand cmd=new SqlCommand("testProcedure_AX",con);
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) cmd.CommandType=CommandType.StoredProcedure;
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) con.Open();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) try
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) {
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) SqlDataReader dr=cmd.ExecuteReader();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) while(dr.Read())
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) {
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) if(dr[0].ToString()=="")
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) {
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) arrayCName.Add(dr[1].ToString());
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) }
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) }
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) con.Close();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) return "OK!";
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) }
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) catch(Exception ex)
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) {
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) con.Close();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) return ex.ToString();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) }
(tng) (tng) (tng) (tng) (tng) (tng) (tng) }
?其实是把以?br />SqlCommand cmd=new SqlCommand("select userID from USERS order by userid desc",con);
中的SQL语句替换为存储过E名,再把cmd的类型标注ؓ(f)CommandType.StoredProcedure(存储q程)
⑤写个带参数的存储过E吧,上面q个单得有点惨不忍睹,不过q是蛮实用的.
参数带就带两,一个的没面?太小家子气了(jin).
CREATE PROCEDURE dbo.AXzhz
/*
q里写注?br />*/
@startDate varchar(16),
@endDate varchar(16)
AS
(tng)select id (tng) from table_AX where commentDateTime>@startDate and commentDateTime<@endDate order by contentownerid DESC
?@startDate varchar(16)是声明@startDate q个变量,多个变量名间用?】隔开.后面的SQL可以用这个变量了(jin).
⑥我怎么在ASP.NET中调用这个带参数的存储过E?
(tng)public static string GetCustomerCNameCount(string startDate,string endDate,ref DataSet ds)
{
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) SqlConnection con=ADConnection.createConnection();
//-----------------------注意q一D?-------------------------------------------------------------------------------------------------------
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) SqlDataAdapter da=new SqlDataAdapter("AXzhz",con);
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) para0=new SqlParameter("@startDate",startDate);
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) para1=new SqlParameter("@endDate",endDate);
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) da.SelectCommand.Parameters.Add(para0);
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) da.SelectCommand.Parameters.Add(para1);
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) da.SelectCommand.CommandType=CommandType.StoredProcedure;
//-------------------------------------------------------------------------------------------------------------------------------
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) try
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) {
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) con.Open();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) da.Fill(ds);
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) con.Close();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) return "OK";
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) }
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) catch(Exception ex)
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) {
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) return ex.ToString();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) } (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)
(tng) (tng) (tng) (tng) (tng) (tng) (tng) }
?把命令的参数dq去,O(jin)K?br />鸟的,改字体颜色的东西太垃圾了(jin),改不?大家凑活着?
⑦我q想看看SQL命o(h)执行成功?jin)没?
注意看下面三行红色的语句
CREATE PROCEDURE dbo.AXzhz
/*
(tng) @parameter1 用户?br /> (tng) @parameter2 新密?br />*/
@password nvarchar(20),
@userName nvarchar(20)
AS
declare @err0 int
update WL_user set password=@password where UserName=@userName
set @err0=@@error
select (tng) @err0 as err0
?先声明一个整型变量@err0,再给其赋gؓ(f)@@error(q个是系l自动给出的语句是否执行成功,0为成?其它为失?,最后通过select把它选择出来,某位高h说可以通过Returnq回,出本h的认知范?俺暂时不?以后再补充吧
⑧那怎么从后台获得这个执行成功与否的值呢?
下面q段代码可以告诉你答?
(tng) (tng) (tng) public static string GetCustomerCName()
(tng) (tng) (tng) (tng) (tng) (tng) (tng) {
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) SqlConnection con=ADConnection.createConnection();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) SqlCommand cmd=new SqlCommand("AXzhz",con);
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) cmd.CommandType=CommandType.StoredProcedure;
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) para0=new SqlParameter("@startDate","2006-9-10");
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) para1=new SqlParameter("@endDate","2006-9-20");
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) da.SelectCommand.Parameters.Add(para0);
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) da.SelectCommand.Parameters.Add(para1);
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) con.Open();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) try
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) {
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) Int32 re=(int32)cmd.ExecuteScalar();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) con.Close();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) if (re==0)
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) return "OK!";
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) else
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) return "false";
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) }
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) catch(Exception ex)
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) {
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) con.Close();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) return ex.ToString();
(tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) }
(tng) (tng) (tng) (tng) (tng) (tng) (tng) }
?是通过SqlCommand的ExecuteScalar()Ҏ(gu)取回q个?q句话是从MSDN上找?为改?
(tng) (tng) (tng) (tng) int re=(int)cmd.ExecuteScalar(); (tng) 99%正确,现在没时间验?期待(zhn)的试!!!
⑨我要根据传入的参数判断执行哪条SQL语句!!~
下面q个存储q程可以满我们的要?竟然是Pascal/VB的写?Begin----End ,不是{},,,对用C#的我来说,q个语法有点恶心(j).........
ALTER PROCEDURE dbo.selectCustomerCNameCount
@customerID int
AS
if @customerID=-1
(tng)begin
(tng)select contentownerid ,userCName,count(*) as countAll from view_usercomment group by contentownerid,userCName order by contentownerid DESC
(tng)end
else
(tng)begin
(tng)select contentownerid ,userCName,count(*) as countAll from view_usercomment where contentownerid=@customerID group by contentownerid,userCName order by contentownerid DESC
(tng)end
好了(jin),俺的水^只止于此,也够菜鸟们喝一壶的?q有更多东西{着我们d?无尽的征?!!!!!!!!!!
from: http://www.knowsky.com/340678.html
weidagang2046 2006-10-27 12:14 发表评论
]]>一、烦(ch)引的概念
(tng) (tng) (tng) (tng) (tng) (tng) (tng) 索引是加快(g)索表中数据的Ҏ(gu)?a >数据?/a>的烦(ch)引类g书籍的烦(ch)引。在书籍中，索引允许用户不必阅完整个书pq速地扑ֈ所需要的信息。在数据库中Q烦(ch)引也允许数据库程序迅速地扑ֈ表中的数据，而不必扫描整个数据库?/p>
二、烦(ch)引的特点
(tng) (tng) (tng) 1.索引可以加快数据库的(g)索速度
(tng) (tng) (tng) 2.索引降低?jin)数据库插入、修攏V删除等l护d的速度
(tng) (tng) (tng) 3.索引创徏在表上，不能创徏在视图上
(tng) (tng) (tng) 4.索引既可以直接创建，也可以间接创?
(tng) (tng) (tng) 5.可以在优化隐藏中Q用烦(ch)?
(tng) (tng) (tng) 6.使用查询处理器执行SQL语句Q在一个表上，一ơ只能用一个烦(ch)?
(tng) (tng) (tng) 7.其他
三、烦(ch)引的优点
(tng) (tng) (tng) 1.创徏唯一性烦(ch)引，保证数据库表中每一行数据的唯一?br /> (tng) (tng) (tng) 2.大大加快数据的检索速度Q这也是创徏索引的最主要的原?br /> (tng) (tng) (tng) 3.加速表和表之间的连接，特别是在实现数据的参考完整性方面特别有意义?br /> (tng) (tng) (tng) 4.在用分l和排序子句q行数据(g)索时Q同样可以显著减查询中分组和排序的旉?br /> (tng) (tng) (tng) 5.通过使用索引Q可以在查询的过E中使用优化隐藏器，提高pȝ的性能?/p>
四、烦(ch)引的~点
(tng) (tng) (tng) 1.创徏索引和维护烦(ch)引要耗费旉Q这U时间随着数据量的增加而增?br /> (tng) (tng) (tng) 2.索引需要占物理I间Q除?jin)数据表占数据空间之外，每一个烦(ch)引还要占一定的物理I间Q如果要建立聚簇索引Q那么需要的I间׃(x)更大
(tng) (tng) (tng) 3.当对表中的数据进行增加、删除和修改的时候，索引也要动态的l护Q降低了(jin)数据的维护速度
五、烦(ch)引分c?br /> (tng) (tng) (tng) 1.直接创徏索引和间接创建烦(ch)?br /> (tng) (tng) (tng) 直接创徏索引Q?CREATE INDEX mycolumn_index ON mytable (myclumn)
(tng) (tng) (tng) 间接创徏索引Q定义主键约束或者唯一性键U束Q可以间接创建烦(ch)?br /> (tng) (tng) (tng) 2.普通烦(ch)引和唯一性烦(ch)?br /> (tng) (tng) (tng) 普通烦(ch)引：(x)CREATE INDEX mycolumn_index ON mytable (myclumn)
(tng) (tng) (tng) 唯一性烦(ch)引：(x)保证在烦(ch)引列中的全部数据是唯一的，对聚烦(ch)引和非聚烦(ch)引都可以使用
(tng) (tng) (tng) CREATE UNIQUE COUSTERED INDEX myclumn_cindex ON mytable(mycolumn)
(tng) (tng) (tng) 3.单个索引和复合烦(ch)?br /> (tng) (tng) (tng) 单个索引Q即非复合烦(ch)?br /> (tng) (tng) (tng) 复合索引Q又叫组合烦(ch)引，在烦(ch)引徏立语句中同时包含多个字段名，最?6个字D?br /> (tng) (tng) (tng) CREATE INDEX name_index ON username(firstname,lastname)
(tng) (tng) (tng) 4.聚簇索引和非聚簇索引(聚集索引Q群集烦(ch)?
(tng) (tng) 聚簇索引Q物理烦(ch)引，与基表的物理序相同Q数据值的序L按照序排列
(tng) (tng) (tng) CREATE CLUSTERED INDEX mycolumn_cindex ON mytable(mycolumn) WITH
(tng) (tng) (tng) ALLOW_DUP_ROW(允许有重复记录的聚簇索引)
(tng) (tng) 非聚烦(ch)引：(x)CREATE UNCLUSTERED INDEX mycolumn_cindex ON mytable(mycolumn)
六、烦(ch)引的使用
(tng) (tng) 1.当字D|据更新频率较低，查询使用频率较高q且存在大量重复值是使用聚簇索引
(tng) (tng) (tng) 2.l常同时存取多列Q且每列都含有重复值可考虑建立l合索引
(tng) (tng) (tng) 3.复合索引的前导列一定好控制好，否则无法起到索引的效果。如果查询时前导列不在查询条件中则该复合索引不会(x)被用。前导列一定是使用最频繁的列
(tng) (tng) (tng) 4.多表操作在被实际执行前，查询优化器会(x)Ҏ(gu)q接条gQ列出几l可能的q接Ҏ(gu)q从中找出系l开销最的最x案。连接条件要充䆾考虑带有索引的表、行数多的表Q内外表的选择可由公式Q外层表中的匚w行数*内层表中每一ơ查扄ơ数定Q乘U最ؓ(f)最x?br /> (tng) (tng) (tng) 5.where子句中对列的M操作l果都是在sqlq行旉列计算得到的，因此它不得不q行表搜索，而没有用该列上面的索引Q如果这些结果在查询~译时就能得刎ͼ那么可以被sql优化器优化，使用索引Q避免表搜烦(ch)(例：(x)select * from record where substring(card_no,1,4)=?378?
&& select * from record where card_no like ?378%?M对列的操作都导致表扫描Q它包括数据库函数、计表辑ּ{等Q查询时要尽可能操作移至等号右?br /> (tng) (tng) (tng) 6.where条g中的’in’在逻辑上相当于’or’，所以语法分析器?x)将in ('0','1')转化为column='0' or column='1'来执行。我们期望它?x)根据每个or子句分别查找Q再结果相加，q样可以利用column上的索引Q但实际上它却采用了(jin)"or{略"Q即先取出满x个or子句的行Q存入(f)时数据库的工作表中，再徏立唯一索引以去掉重复行Q最后从q个临时表中计算l果。因此，实际q程没有利用column上烦(ch)引，q且完成旉q要受tempdb数据库性能的媄(jing)响。in、or子句怼(x)使用工作表，使烦(ch)引失效；如果不生大量重复|可以考虑把子句拆开Q拆开的子句中应该包含索引
(tng) (tng) (tng) 7.要善于用存储过E，它sql变得更加灉|和高?br />
from: http://www.knowsky.com/339315.html
weidagang2046 2006-10-27 12:13 发表评论
]]>1 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 衣服
2 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 裤子
5 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 帽子
10 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 鞋子
表productInfo有如下记?
productID (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)productName (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)parentID (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) clickNum
1 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 男士衣服 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)1 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)90 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) --衣服cd中这条记录的点击率最?br />2 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 奛_衣服 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)1 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 80
3 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 男士裤子 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)2 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 70
4 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 奛_裤子 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)2 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 90 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) --裤子cd中这条记录点ȝ最?br />5 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 男士帽子 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)5 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)15
6 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 奛_帽子 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)5 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)30 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)--帽子cd中这条点ȝ最?br />7 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 男士鞋子 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)10 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 65 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)--鞋子cd中这条点ȝ最?br />8 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 奛_鞋子 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)10 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)52
9 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) 奛_鞋子1 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)10 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)54
现在要求分别把衣?裤子,帽子,鞋子q些cd中点ȝ最高的一条记录找出来,然后再降序排?l果应如?
productID (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) productName (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) clickNum
1 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)男士衣服 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)90
4 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)奛_裤子 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)90
7 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)男士鞋子 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)65
6 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)奛_帽子 (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)30
select (tng)* (tng)from (tng)goods (tng)as (tng)g1 (tng)where (tng) (tng) (tng) (tng) (tng)not (tng)exists (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)(select (tng)* (tng)from (tng)goods (tng)as (tng)g2 (tng)where (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng) (tng)g1.parentId (tng)= (tng)g2.parentId (tng)and (tng)g2.clickNum (tng)> (tng)g1.clickNum (tng) (tng) (tng) (tng))weidagang2046 2006-08-15 09:16 发表评论
]]>解决Ҏ(gu)Q?/p>
- 启动SQLSERVER企业理器，选择要进行认证模式设|的服务器。右击该服务器，在弹?gu)单中选择属性，SQL SERVER弹出属性对话框
2. 在属性对话框中选择安全性选项Q在w䆾验证处选择“SQL Server和W(xu)indows”，然后定?br />
from: http://www.lunji.com/faq/login_error.htm
weidagang2046 2006-08-10 19:49 发表评论
]]>(1) 到Postgresql的官方网?A >http://www.postgresql.org/下蝲安装文g?BR>(2) q行安装E序Q本文假讑֮装\径选C:\pgsqlQdata路径选D:\pgsql\dataQ注意安装过E中不要选install as service?BR>(3) C:\pgsql\bin加入PATH环境变量?BR>(4) d用户postgresQ本文假讑֯码ؓ(f)1234?BR>(5) 用postgres帐号初始化数据库集群。可以先注销当前用户再用postgres帐号登陆Q也可以用命令runas /user:postgres cmd切换到postgres帐号Q然后在命o(h)提示W下面输入：(x)initdb -E UNICODE --locale=C -D d:\pgsql\data。注意：(x)要先建立d:\pgsql\data目录?BR>(6) 安装服务Q用Administrator帐号来做Qƈ启动Qpg_ctl register -N PostgreSQL -U postgres -P 1234 -D d:\pgsql\data
(7) 用postgres帐号q行Qcreateuser -a Administrator为数据库d一个超U用P以后的操作都可以用Administrator帐号来完成，不必切换到postgres帐号?/FONT>
weidagang2046 2005-04-19 09:26 发表评论
]]>