??xml version="1.0" encoding="utf-8" standalone="yes"?>成年网站在线,国产小视频在线,9久草视频在线视频精品http://www.aygfsteel.com/kylixlu/category/28124.htmlzh-cnThu, 28 Feb 2008 09:30:01 GMTThu, 28 Feb 2008 09:30:01 GMT60修复ORACLE92i TNS-12545: 因目标主机或对象不存在,q接p| 错误http://www.aygfsteel.com/kylixlu/archive/2008/02/27/182403.html陆昱?/dc:creator>陆昱?/author>Wed, 27 Feb 2008 02:16:00 GMThttp://www.aygfsteel.com/kylixlu/archive/2008/02/27/182403.htmlhttp://www.aygfsteel.com/kylixlu/comments/182403.htmlhttp://www.aygfsteel.com/kylixlu/archive/2008/02/27/182403.html#Feedback0http://www.aygfsteel.com/kylixlu/comments/commentRss/182403.htmlhttp://www.aygfsteel.com/kylixlu/services/trackbacks/182403.html
    l查资料,发现是主机名可能解析有问?后来在D:\oracle\ora92\network\admin下打开listener.ora文g后将HOST后的L?(ADDRESS = (PROTOCOL = TCP)(HOST = SUZSOFT-8CB5627)(PORT = 1521))
ҎIP卛_解决上面遇到问题 (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.7.115)(PORT = 1521))



]]>
Oracle9i中的一个特D等待事?/title><link>http://www.aygfsteel.com/kylixlu/archive/2008/02/15/179988.html</link><dc:creator>陆昱?/dc:creator><author>陆昱?/author><pubDate>Thu, 14 Feb 2008 17:03:00 GMT</pubDate><guid>http://www.aygfsteel.com/kylixlu/archive/2008/02/15/179988.html</guid><wfw:comment>http://www.aygfsteel.com/kylixlu/comments/179988.html</wfw:comment><comments>http://www.aygfsteel.com/kylixlu/archive/2008/02/15/179988.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.aygfsteel.com/kylixlu/comments/commentRss/179988.html</wfw:commentRss><trackback:ping>http://www.aygfsteel.com/kylixlu/services/trackbacks/179988.html</trackback:ping><description><![CDATA[很多Z许ƈ不清楚,null event其实不是IZӞ因ؓ不是没有{待事gQ而是Oracle忘记了刚才等待的事g的名字具体是什么了Q但却保留了该事件的真实情况。Oracle的开发h员直?.2.0.3才更Cq些事g的名U? <p><font face="Times New Roman">  那是不是我们每当遇到性能问题的时候都要patch?.2.0.3呢?</font></p> <p><font face="Times New Roman">  我们已经知道他的真实情况依然在v$session_wait的p1、p2、p3参数里体玎ͼ所以,我们可以Ҏq些参数Q找个null eventI竟是什么等待事件?/font></p> <p><font face="Times New Roman">  相关信息Q?/font></p> <p><font face="Times New Roman">  1. lck processes to pick up extra or missed 'posts' QmessagesQ?/font></p> <p><font face="Times New Roman">  in all cases that can be identified the wait time is zeroQ?/font></p> <p><font face="Times New Roman">  although on most ports this is changed to 1/100th second in</font></p> <p><font face="Times New Roman">  order to force the process to be rescheduled.</font></p> <p><font face="Times New Roman">  2. multiple db writers.</font></p> <p><font face="Times New Roman">  two casesQ?/font></p> <p><font face="Times New Roman">  - when the master has sent i/o requests to the slavesQ?it</font></p> <p><font face="Times New Roman">  waits on this event for up to 6 seconds until the slaves</font></p> <p><font face="Times New Roman">  signal that the i/o is complete.</font></p> <p><font face="Times New Roman">  - the slaves wait on this event for up to 3 seconds whilst</font></p> <p><font face="Times New Roman">  waiting for requests from the master db writer.</font></p> <p><font face="Times New Roman">  目前已经被证实的会涉及到null event</font></p> <p><font face="Times New Roman">  的等待事件还有有sql.net message to client?/font></p> <p><font face="Times New Roman">  db file scattered Qor sequentialQ?read</font></p> <img src ="http://www.aygfsteel.com/kylixlu/aggbug/179988.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.aygfsteel.com/kylixlu/" target="_blank">陆昱?/a> 2008-02-15 01:03 <a href="http://www.aygfsteel.com/kylixlu/archive/2008/02/15/179988.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>Oracle 11g最有特点的五大Ҏ?/title><link>http://www.aygfsteel.com/kylixlu/archive/2008/02/15/179986.html</link><dc:creator>陆昱?/dc:creator><author>陆昱?/author><pubDate>Thu, 14 Feb 2008 17:01:00 GMT</pubDate><guid>http://www.aygfsteel.com/kylixlu/archive/2008/02/15/179986.html</guid><wfw:comment>http://www.aygfsteel.com/kylixlu/comments/179986.html</wfw:comment><comments>http://www.aygfsteel.com/kylixlu/archive/2008/02/15/179986.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.aygfsteel.com/kylixlu/comments/commentRss/179986.html</wfw:commentRss><trackback:ping>http://www.aygfsteel.com/kylixlu/services/trackbacks/179986.html</trackback:ping><description><![CDATA[与无压羃格式下存储数据相比,新的Oracle数据压羃技术能够确保以较小的开销节省三倍以上的盘存储I间。这一Ҏ仅节省磁盘空间要h更大的优势,因ؓ它能够企业节约更多的开支,以便有更多的资金来mqC? <p><font face="Times New Roman">  自动诊断知识库(Automatic Diagnostic RepositoryQADRQ是专门针对严重错误的知识库。该知识库基本上能够自动完成一些以往需要由数据库管理员来手动完成的操作?/font></p> <p><font face="Times New Roman">  作ؓADR的一部分QSQL性能分析器(SQL Performance AnalyzerQSPAQ是最让h惊喜的特性之一。SQL性能分析器是一个整体调整工P理员可以通过该工具在数据库上定义和重演(replayQ?一个典型的工作负蝲Q之后管理员可以调节整体参数来数据库尽快的辑ֈ最x能——而这一d同样也是许多q以来由数据库管理员手动完成的?/font></p> <p><font face="Times New Roman">  ׃获得了最优的初始参数Q数据库理员就不需要调整数以万计的SQL语句。管理员需要做的就是给定一个典型的负蝲 Q由SAPҎ历史记录来决定SQL的最l设|,而不用管理员来检哪一个SQL讄是最合理的?/font></p> <p><font face="Times New Roman">  多年以来Q甲骨文公司一直在努力完成地另一个新Ҏ便?#8220;联机更新”Q在不down机的情况下更新YӞ。实际上Q很难从软g工程的角度来设计一个运行时能自动升U的软g。由于真正的应用集群QReal Application Clusters QRACQ特性,甲骨文公司再一ơ对其他的数据库供应商造成了更大的压力。在实际的用过E中Q数据库产品的用hL希望产品有持l的高可用性,qƈ不是说只需满下次补丁更新之前?q的旉够了?/font></p> <p><font face="Times New Roman">  自动内存理Ҏ可以追Ҏ源至Oracle 9iQ那时甲骨文公司推出首款自动调节存储池的工具。AMM工具其实是一U探机制。实际上QOracle 11g 有很多随问存储池Q当AMM探测到某个存储池中已满时Q它整个RAM从一个区域分配到其他相对合适的区域?/font></p> <img src ="http://www.aygfsteel.com/kylixlu/aggbug/179986.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.aygfsteel.com/kylixlu/" target="_blank">陆昱?/a> 2008-02-15 01:01 <a href="http://www.aygfsteel.com/kylixlu/archive/2008/02/15/179986.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>用SQL Server 2005 实现l果集分?http://www.aygfsteel.com/kylixlu/archive/2008/01/20/176624.html陆昱?/dc:creator>陆昱?/author>Sun, 20 Jan 2008 12:21:00 GMThttp://www.aygfsteel.com/kylixlu/archive/2008/01/20/176624.htmlhttp://www.aygfsteel.com/kylixlu/comments/176624.htmlhttp://www.aygfsteel.com/kylixlu/archive/2008/01/20/176624.html#Feedback0http://www.aygfsteel.com/kylixlu/comments/commentRss/176624.htmlhttp://www.aygfsteel.com/kylixlu/services/trackbacks/176624.html介绍
有了SQL Server 2005之后Q我们用分|询比老版本容易多了。在本文中,我将主要用到的是NorthWind数据库,所以你也可以仿照编写我所列D的范例。我量使例子简单化;因ؓM复杂的东襉K会都会造成h。我从“传统”的方法着手,比如QSELECT, TOPQ然后慢慢进入具体的SQL Server 2005 分页的例子?br /> 背景
我常怼被问到这L一个问题或者说一pdq样的问题,“你如何在SQL中进行分?在有很多个记录的情况下,你又如何做,比如10000个记录或者更多呢Q?br /> 我思烦着{案。更切地说Q我考虑了更多的问题q且我都认真L考,“q必定是一个普的问题Q每一个开发h员必d理或者说解决的。具有非常大的数据库集的工作和分大是怎样的?从多U表所得到的结果集又是如何Q?#8221;
因此Q我军_具体l合SQL Server 2005来研I这些问题。下面的Ҏ是至今ؓ止最Ҏ的,采纳。但是这是非常罕见的Qƈ非易事?br />  
select * from mytable
Where ID between20and30
 
SQL Top
SQL TopQ从l果集返回记录)非常善于从结果集的每个尾部返回大量的记录?br /> 下面的例子通过命oqty获得了前10名顾客。在论坛上这是一个非常普骗的问题。尽TOP也可以拉动一定百分比的记录,但是我们q里不讨论?br />  
selecttop10 * from customers -- This is a very basic example.
selectTOP10 Customers.CustomerID, Customers.CompanyName, count(*) OrderCount
from Customers innerjoin Orders on Orders.CustomerID = Customers.CustomerID
GROUPBY Customers.CustomerID, Customers.CompanyName
ORDERBY OrderCount DESC
 
q是很有用的。当你要把记录从11拉到20Ӟ你就可以使用临时表?br />  
-- SELECT First 30 records in to Temp table
SELECTTOP30 * INTO
#TEMP
from Customers
ORDERBY CompanyName ASC
 
--Select Bottom 10 records in another temp table
 
SELECTTOP10 *
INTO #TEMP2
from #Temp
ORDERBY CompanyName DESC
 
-- GET THE RECORDS
 
SELECT * FROM #TEMP2
 
q对数前几个页面或者前几个用户是种惩罚。如果拥有这L用户Q他们想从一一之后返回页面,你将以1000条记录返?0条来l束Q这是非怽效的。你可以在第一个时表中内|一个n份,然后用一个SELECT声明来作替代?br /> TOP的替?br /> 有一个这LTOP替代Q它使用的是rowcountQ行计数Q。用行计数要小心。如果它不关闭的话,你陷入各U各L困境?br /> SETrowcount10
SELECT * from Customers
ORDERBY CompanyName
WITH, ROW_NUMBER Q行敎ͼand OVER
q对SQL Server 2005来说非常新鲜q且看上去非常有用。下面一个例子显CZ一个结果集得到20?9条记录。刚开始,我有一Ҏ奇,但是我浏览了查询器后我发现它是如此简单?br /> With Cust AS
    ( SELECT CustomerID, CompanyName,
    ROW_NUMBER() OVER (orderby CompanyName) as RowNumber
    FROM Customers )
select *
from Cust
Where RowNumber Between20and30
SQL Server 2005的WITH指定了一个时命名的l果Q很像SQL Server以前版本中的临时表。但是,输入部分是ROW_NUMBER和OVER声明Q它Ҏ公司的名U在每组中创数。这像通过命o条文向时表d一个n份种子?br /> 我希望你赞成我的看法。如果不Q运行代码ƈ查看l果集。对大表来说速度真的非常?表的速度过250Q?00条记录,Ҏ我留下了深刻的印象?br /> 一h合到储存q程?br /> 现在我们把它一h合到储存q程Q这个储存过E我们可以通过应用E序来用。我不打展C?NET Datagrid或者相似的控gQ因为是本文探讨范围之外。下面看到的储存q程使用了灵zȝ面大小和页面数目,所以你可以随意地选择M面。这P如果你想跌前十去L某一条记录就非常方便了。下面的例子是从W一开始分늚Q而不是从W?,但也可以随意更改?br />  
CREATEPROC GetCustomersByPage
 
@PageSize int, @PageNumber int
 
AS
 
Declare @RowStart int
Declare @RowEnd int
 
if @PageNumber > 0
Begin
 
SET @PageNumber = @PageNumber -1
 
SET @RowStart = @PageSize * @PageNumber + 1;
SET @RowEnd = @RowStart + @PageSize - 1 ;
 
With Cust AS
     ( SELECT CustomerID, CompanyName,
       ROW_NUMBER() OVER (orderby CompanyName) as RowNumber
       FROM Customers )
 
select *
from Cust
Where RowNumber >= @RowStart and RowNumber <= @RowEnd end
 
END
q行q个E序Q仅需指定面大小和页数目(GetCustomersByPage, @PageSize and @PageNumber)Q代码如下:
exec GetCustomersByPage 10, 1


]]>
修复oracle 9i Listener出错http://www.aygfsteel.com/kylixlu/archive/2008/01/13/174961.html陆昱?/dc:creator>陆昱?/author>Sun, 13 Jan 2008 04:38:00 GMThttp://www.aygfsteel.com/kylixlu/archive/2008/01/13/174961.htmlhttp://www.aygfsteel.com/kylixlu/comments/174961.htmlhttp://www.aygfsteel.com/kylixlu/archive/2008/01/13/174961.html#Feedback0http://www.aygfsteel.com/kylixlu/comments/commentRss/174961.htmlhttp://www.aygfsteel.com/kylixlu/services/trackbacks/174961.html出错状况:
我用的是Windows XPQ在“服务”中启?#8220;OracleOraHome90TNSListener”p|Q说?br /> ?本地计算?无法启动 OracleOraHome90TNSListener 服务?br />
错误 3: pȝ找不到指定的路径?br />
于是Q我在CMD中输?#8220;LSNRCTL”

LSNRCTL for 32-bit Windows: Version 9.0.1.1.1 - Production on 28-1?-2005 10:56
:54

Copyright (c) 1991, 2001, Oracle Corporation.  All rights reserved.

Ƣ迎来到LSNRCTLQ请键入"help"以获得信息?br />
LSNRCTL> start
启动tnslsnrQ请E?..

Failed to start service, error 3.
TNS-12560: TNS: 协议适配器错?br /> TNS-00530: 协议适配器错?br />   32-bit Windows Error: 3: No such process
 
 
解决办法:
1.你修改了L?如果是的?你可以把L名改回来,然后重v计算机后,可以找到监听程序了.
2.׃你的错误删除了监听程序的路径,要恢复很?点开?>q行输入"regedit"然后在查N输入OracleOraHome90TNSListenerL?如果扑ֈ后你p增加一ImagePath,定义成字W集,路径? "盘符:\oracle\ora90\bin\tnslsnr".d完后l箋按F3来找!修改同上.臛_搜烦完毕为止!此方法成功几率ؓ90%以上


]]>
SQL中NULL的问?/title><link>http://www.aygfsteel.com/kylixlu/archive/2007/12/26/170527.html</link><dc:creator>陆昱?/dc:creator><author>陆昱?/author><pubDate>Wed, 26 Dec 2007 03:17:00 GMT</pubDate><guid>http://www.aygfsteel.com/kylixlu/archive/2007/12/26/170527.html</guid><wfw:comment>http://www.aygfsteel.com/kylixlu/comments/170527.html</wfw:comment><comments>http://www.aygfsteel.com/kylixlu/archive/2007/12/26/170527.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.aygfsteel.com/kylixlu/comments/commentRss/170527.html</wfw:commentRss><trackback:ping>http://www.aygfsteel.com/kylixlu/services/trackbacks/170527.html</trackback:ping><description><![CDATA[<p>e.g : column_name IS NULL不可以写成column_name=NULL;除了IS[NOT] NULL之外Q空g满M查找条gQ如果NULL参与术q算Q则l果可视为FalseQ在SQL-92中可看成UNKNOWN;如果NULL参与聚集q算Q则除count(*)之外其他聚集函数都忽略NULL?/p> <img src ="http://www.aygfsteel.com/kylixlu/aggbug/170527.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.aygfsteel.com/kylixlu/" target="_blank">陆昱?/a> 2007-12-26 11:17 <a href="http://www.aygfsteel.com/kylixlu/archive/2007/12/26/170527.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>Select语句的执行步?/title><link>http://www.aygfsteel.com/kylixlu/archive/2007/12/26/170521.html</link><dc:creator>陆昱?/dc:creator><author>陆昱?/author><pubDate>Wed, 26 Dec 2007 02:49:00 GMT</pubDate><guid>http://www.aygfsteel.com/kylixlu/archive/2007/12/26/170521.html</guid><wfw:comment>http://www.aygfsteel.com/kylixlu/comments/170521.html</wfw:comment><comments>http://www.aygfsteel.com/kylixlu/archive/2007/12/26/170521.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.aygfsteel.com/kylixlu/comments/commentRss/170521.html</wfw:commentRss><trackback:ping>http://www.aygfsteel.com/kylixlu/services/trackbacks/170521.html</trackback:ping><description><![CDATA[<span style="font-size: 14pt">当执行Select语句ӞDBMS的执行步骤表C如下:<br /> </span><br /> <span style="font-size: 12pt; font-family: 宋体">(1)执行FORM子句,ҎFROM子句中的一个或多个表创建工作表。如果在FROM子句中有两个或多个表QDBMS对表进行交叉连接,作ؓ工作表?br style="font-family: " /> <br style="font-family: " /> (2)如果有WHERE子句QDBMSWHERE子句列出的搜索条件作用于步骤(1)生成的工作表。DBMS保留那些满x索条件的行,删除那些不满x索条件的行?br style="font-family: " /> <br style="font-family: " /> (3)如果有GROUP BY子句QDBMS步?2)生成的结果表中的行分成多个组Q每个组所有行的group_by_expression字段h相同的|DBMS每l减到单行Q然后将其添加到新的l果表中?br style="font-family: " /> <br style="font-family: " /> (4)如果有HAVING子句QDBMSHAVING子句列出的搜索条件作用于步骤(3)生成?#8220;l合”表中的每一行。DBMS保留那些满x索条件的行,删除那些不满x索条件的行?br style="font-family: " /> <br style="font-family: " /> (5)SELECT子句作用于结果表。删除结果表中不包含在select_list中的列。如果SELECT子句包含DISTINCT关键字,DBMS从l果中删除重复的行?br /> <br /> (6)如果有ORDER BY子句Q按指定的排序规则对l果q行排序?br /> <br /> (7)对于交互式的SELECT语句Q在屏幕上显C结果,对于嵌入式SQLQ用游标将l果传递给宿主E序中?br /> <br />   以上是SQL SELECT语句的基本执行过E?/span> <img src ="http://www.aygfsteel.com/kylixlu/aggbug/170521.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.aygfsteel.com/kylixlu/" target="_blank">陆昱?/a> 2007-12-26 10:49 <a href="http://www.aygfsteel.com/kylixlu/archive/2007/12/26/170521.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>SQLServer和Oracle常用函数Ҏhttp://www.aygfsteel.com/kylixlu/archive/2007/12/24/169942.html陆昱?/dc:creator>陆昱?/author>Mon, 24 Dec 2007 01:59:00 GMThttp://www.aygfsteel.com/kylixlu/archive/2007/12/24/169942.htmlhttp://www.aygfsteel.com/kylixlu/comments/169942.htmlhttp://www.aygfsteel.com/kylixlu/archive/2007/12/24/169942.html#Feedback0http://www.aygfsteel.com/kylixlu/comments/commentRss/169942.htmlhttp://www.aygfsteel.com/kylixlu/services/trackbacks/169942.html 1.l对?
S:select abs(-1) value
O:select abs(-1) value from dual

2.取整(?
S:select ceiling(-1.001) value
O:select ceil(-1.001) value from dual

3.取整Q小Q?
S:select floor(-1.001) value
O:select floor(-1.001) value from dual

4.取整Q截取)
S:select cast(-1.002 as int) value
O:select trunc(-1.002) value from dual

5.四舍五入
S:select round(1.23456,4) value 1.23460
O:select round(1.23456,4) value from dual 1.2346

6.e为底的幂
S:select Exp(1) value 2.7182818284590451
O:select Exp(1) value from dual 2.71828182

7.取e为底的对?
S:select log(2.7182818284590451) value 1
O:select ln(2.7182818284590451) value from dual; 1

8.?0为底Ҏ
S:select log10(10) value 1
O:select log(10,10) value from dual; 1

9.取^?
S:select SQUARE(4) value 16
O:select power(4,2) value from dual 16

10.取^Ҏ
S:select SQRT(4) value 2
O:select SQRT(4) value from dual 2

11.求Q意数为底的幂
S:select power(3,4) value 81
O:select power(3,4) value from dual 81

12.取随机数
S:select rand() value
O:select sys.dbms_random.value(0,1) value from dual;

13.取符?
S:select sign(-8) value -1
O:select sign(-8) value from dual -1

14.圆周?
S:SELECT PI() value 3.1415926535897931
O:不知?

15.sin,cos,tan 参数都以弧度为单?
例如Qselect sin(PI()/2) value 得到1QSQLServerQ?

16.Asin,Acos,Atan,Atan2 q回弧度

17.弧度角度互换(SQLServerQOracle不知?
DEGREESQ弧?〉角?
RADIANSQ角?〉弧?
数值间比较Q?br /> 18. 求集合最大?
S:select max(value) value from
(select 1 value
union
select -2 value
union
select 4 value
union
select 3 value)a

O:select greatest(1,-2,4,3) value from dual

19. 求集合最?
S:select min(value) value from
(select 1 value
union
select -2 value
union
select 4 value
union
select 3 value)a

O:select least(1,-2,4,3) value from dual

20.如何处理null?F2中的null?0代替)
S:select F1,IsNull(F2,10) value from Tbl
O:select F1,nvl(F2,10) value from Tbl

21.求字W序?
S:select ascii('a') value
O:select ascii('a') value from dual

22.从序h字符
S:select char(97) value
O:select chr(97) value from dual

23.q接
S:select '11'+'22'+'33' value
O:select CONCAT('11','22')  33 value from dual

23.子串位置 --q回3
S:select CHARINDEX('s','sdsq',2) value
O:select INSTR('sdsq','s',2) value from dual

23.模糊子串的位|?--q回2,参数L中间%则返?
S:select patindex('%d%q%','sdsfasdqe') value
O:oracle没发玎ͼ但是instr可以通过W四个参数控制出现次?
select INSTR('sdsfasdqe','sd',1,2) value from dual q回6

24.求子?
S:select substring('abcd',2,2) value
O:select substr('abcd',2,2) value from dual

25.子串代替 q回aijklmnef
S:SELECT STUFF('abcdef', 2, 3, 'ijklmn') value
O:SELECT Replace('abcdef', 'bcd', 'ijklmn') value from dual

26.子串全部替换
S:没发?
O:select Translate('fasdbfasegas','fa','? ) value from dual

27.长度
S:len,datalength
O:length

28.大小写{?lower,upper

29.单词首字母大?
S:没发?
O:select INITCAP('abcd dsaf df') value from dual

30.左补I格QLPAD的第一个参CؓI格则同space函数Q?
S:select space(10)+'abcd' value
O:select LPAD('abcd',14) value from dual

31.双I格QRPAD的第一个参CؓI格则同space函数Q?
S:select 'abcd'+space(10) value
O:select RPAD('abcd',14) value from dual

32.删除I格
S:ltrim,rtrim
O:ltrim,rtrim,trim

33. 重复字符?
S:select REPLICATE('abcd',2) value
O:没发?

34.发音怼性比?q两个单词返回gP发音相同)
S:SELECT SOUNDEX ('Smith'), SOUNDEX ('Smythe')
O:SELECT SOUNDEX ('Smith'), SOUNDEX ('Smythe') from dual
SQLServer中用SELECT DIFFERENCE('Smithers', 'Smythers') 比较soundex的差
q回0-4Q?为同韻I1最?
日期函数Q?br /> 35.pȝ旉
S:select getdate() value
O:select sysdate value from dual

36.前后几日
直接与整数相加减

37.求日?
S:select convert(char(10),getdate(),20) value
O:select trunc(sysdate) value from dual
select to_char(sysdate,'yyyy-mm-dd') value from dual

38.求时?
S:select convert(char(8),getdate(),108) value
O:select to_char(sysdate,'hh24:mm:ss') value from dual

39.取日期时间的其他部分
S:DATEPART ?DATENAME 函数 Q第一个参数决定)
O:to_char函数 W二个参数决?

参数---------------------------------下表需要补?
year yy, yyyy
quarter qq, q (季度)
month mm, m (m O无效)
dayofyear dy, y (O表星?
day dd, d (d O无效)
week wk, ww (wk O无效)
weekday dw (O不清?
Hour hh,hh12,hh24 (hh12,hh24 S无效)
minute mi, n (n O无效)
second ss, s (s O无效)
millisecond ms (O无效)
----------------------------------------------

40.当月最后一?
S:不知?
O:select LAST_DAY(sysdate) value from dual

41.本星期的某一天(比如星期日)
S:不知?
O:SELECT Next_day(sysdate,7) vaule FROM DUAL;

42.字符串{旉
S:可以直接转或者select cast('2004-09-08'as datetime) value
O:SELECT To_date('2004-01-05 22:09:38','yyyy-mm-dd hh24-mi-ss') vaule FROM DUAL;

43.求两日期某一部分的差Q比如秒Q?
S:select datediff(ss,getdate(),getdate()+12.3) value
O:直接用两个日期相减(比如d1-d2=12.3Q?
SELECT (d1-d2)*24*60*60 vaule FROM DUAL;

44.Ҏ差值求新的日期Q比如分钟)
S:select dateadd(mi,8,getdate()) value
O:SELECT sysdate+8/60/24 vaule FROM DUAL;

45.求不同时区时?
S:不知?
O:SELECT New_time(sysdate,'ydt','gmt' ) vaule FROM DUAL;

-----时区参数,北京在东8区应该是Ydt-------
AST ADT 大西z标准时?
BST BDT 白oh准时?
CST CDT 中部标准旉
EST EDT 东部标准旉
GMT 格林治标准旉
HST HDT 阿拉斯加?夏威h准时?
MST MDT 山区标准旉
NST U芬兰标准时?
PST PDT 太^z标准时?
YST YDT YUKON标准旉




]]>
վ֩ģ壺 | | Զ| | ˮ| ɽ| ƺ| | | żҿ| | | ղ| ɳ| ӳ| | | ͨ| ɽ| ţ| | | Ӱ| ߺ| Թ| | | Ƥ| ͨ| ո| ͤ| | ɽʡ| ֣| Ϫ| ۰| ɽ| ӥ̶| ˫| Դ| |