<a href="javascript:void(0)" onclick="doSomething();returnfalse;">Link</a>
q是一个曾l被多次讨论q的问题Q长期以来，我也一直是q样写的。读?
a href=”javascript:void(0);??avoid the void 之后Q我认同了作者的意见。下面的写法实更合理：
<a href="#" onclick="doSomething();returnfalse;">Link</a>
或?
<script type="javascript"> function doSomething() { //doSomething returnfalse; } </script> <a href="#" onclick="return doSomething();">Link</a>
以往大家不?#"的问题是Q这导致点击链接时面跛_面剙Q但通过 return false 语句得浏览器忽略链接的默认动作，从而避免了此问题?
youngpup 更有意思，他在How to Create Pop-Up Windows 中言辞激烈的倡导大家永远永远永远不要使用 javascript: 伪协议：
Never, ever, ever use the javascript: pseudo-protocol for anything, ever ever ever ever again. Please. Pretty please.
他的解决Ҏ是：
<a href="http://google.com/" onclick="window.open(this.href, 'popupwindow', 'width=400,height=300,scrollbars,resizable'); returnfalse;">
q样的好处就是可以保存到书签或者收藏夹Q可以左键单击，也可以右键用！
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q个问题我以前遇到过Q一直没有详l的LI原因，只是以ؓ是服务器关闭q接太快的原因。今天发现这个问题出的很频繁Q服务器斚w没有改什么，只是上传了新的页面程序而已Q应该不会和服务器有兟뀂在寚w面进行分析，q搜索了一下网上，发现原来是js在documentq没完全load完的时候就试图改变其值导致?br />
因此对js做如下改变：
原jsQ?br />
window.settimeout("go()",500);
function go(){
.......
}
ҎQ?br />
var go_i=window.setInterval("go()",500);
function go(){
if(document.readyState=="complete"){
window.clearInterval(go2_i);
}
else return;
........
}
目的是让他一定要在document完成后才执行那个操作
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今天发现Q如果iframe和parent在同一个三U域名下Q比如都是aa.bb.comQ那设了document.domain反而会造成讉K拒绝?br />
查了下MSDNQ有如下解释Q?br />
Remarks
The property initially returns the host name of the server from which the page is served. The property can be assigned the domain suffix to allow sharing of pages across frames. For example, a page in one frame from home.microsoft.com and a page from www.microsoft.com initially would not be able to communicate with each other. However, by setting the domain property of both pages to the suffix "microsoft.com", you ensure that both pages are considered secure and access is available between the pages.
When you set the domain property, use the domain name determined by the server rather than by the client browser.
All the pages on different hosts must have the domain property explicitly set to the same value to communicate successfully with each other. For example, the value of the domain property of a page on the host microsoft.com would be "microsoft.com" by default. It might seem logical that if you set the domain property of a page on another host named msdn.microsoft.com to "microsoft.com," that the two pages could communicate with each other. However, this is not the case unless you have also explicitly set the domain property of the page on microsoft.com to "microsoft.com".
Furthermore, this property cannot be used to allow cross-frame communication among frames with different domain suffixes. For example, a page in one frame from www.microsoft.com and a page in another frame from www.msn.com would not be able to communicate with each other even if the domain property of both pages was set to the suffix "microsoft.com".
Security Alert Using this property incorrectly can compromise the security of your Web site. Set the domain property only if you must allow cross-domain scripting. Use a value determined on the server. Setting this property to a value determined on the client (like through the location object) could expose your site to attack from another site through Domain Name System (DNS) manipulation. For more information, see Security Considerations: Dynamic HTML.
For more information on domain security, see About Cross-Frame Scripting and Security.
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它是L据库带的slave数据库群里面的一収ͼ每天凌晨定时启动同步数据Q等q上bin-logq全部执行后Q停止同步，q用select * into outfile数据全部导出成文gQƈ且在每周的某一天，清除掉主数据库上已经同步好的bin-logQ以保盘I间不被log占满?br />
为此Q我写了3个脚本，分别执行1、启动mysqlQ追logQ然后停止slaveQ?、导出全部数据库全部文g到文Ӟ3、删除主数据库的log
---------------------------------------------------------------------------------------
#!/bin/bash
#readMasterMysql.sh
CHECK_MYSQL=0
/home/mysql/bin/mysqld_safe &
until [ "$CHECK_MYSQL" = "1" ]
do
sleep 10
CHECK_MYSQL=`/home/mysql/bin/mysql -uroot -e"show slave status"|awk '{if($14==$21)print "1"}'|tail -n1`
done
/home/mysql/bin/mysql -uroot -e"slave stop"
/home/script/backupMysql.sh
/home/mysql/bin/mysqladmin shutdown
WEEK=`date "+%w"`
if [ $WEEK = "5" ]
then
/home/script/purgeLog.sh
fi
------------------------------------------------------------------------------
#!/bin/bash
#purgeLog.sh
LOG_FILE=/home/mysql/data/master.info
DB_SERVER=`sed -n '4p' $LOG_FILE`
DB_USER=`sed -n '5p' $LOG_FILE`
DB_PASS=`sed -n '6p' $LOG_FILE`
DB_LOGFILE=`sed -n '2p' $LOG_FILE`
/home/mysql/bin/mysql -h$DB_SERVER -u$DB_USER -p"$DB_PASS" -e"purge master logs to '$DB_LOGFILE'"
------------------------------------------------------------------------------
#!/bin/bash
#backupMysql.sh
database=$1
table=$2
MYSQL_CLIENT="/home/mysql/bin/mysql -uroot --default-character-set=gbk"
MYSQL_DUMP="/home/mysql/bin/mysqldump -d -uroot --default-character-set=gbk"
OUTPUT_PATH=/date/backup
for databases in `$MYSQL_CLIENT -e "show databases"|grep -v Database`
do
if [ "$#" = "0" -o "$database" = "$databases" ] ; then
mkdir -p -m777 $OUTPUT_PATH/$databases/
$MYSQL_DUMP $databases > $OUTPUT_PATH/$databases/$databases.sql
for tables in `$MYSQL_CLIENT -e "show tables" $databases|grep -v Tables_in_`
do
if [ "$#" = "0" -o "$#" = "1" -o "$table" = "$tables" ] ; then
mv -f $OUTPUT_PATH/$databases/$tables $OUTPUT_PATH/$databases/$tables.old
$MYSQL_CLIENT -e "select * into outfile '$OUTPUT_PATH/$databases/$tables' from $tables" $databases
fi
done
fi
done
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STR_TO_DATE('2003-15-10 00:00:00','%Y-%m-%d %H:%i:%s'); //格式不对Q会q回NULL
to_char(create_time,'yyyy-MM-dd')
DATE_FORMAT(create_time,'%Y-%m-%d')
sysdate
now()或者CURRENT_TIMESTAMP //'1997-12-15 23:50:26',的时候，timestampcd可以指定default CURRENT_TIMESTAMP
sysdate - 7 //7天前
now()-INTERVAL 7 DAY
select * from (select .... where rownum<end) where rownum>start
limit [start,] length
substr(productInfor,1,20)
SUBSTRING('Quadratically',5,6) //SUBSTRING(str,pos,len)
instr(str,substr,pos,index)
instr(str,substr) 或?locate(substr,str,pos)
// 没有相对应的语法Q但一般情况，q个是和substrl合h用的?br />//如果是str="2005-10-01"取中间的10q样的需要，oracle是substr(str,instr(str,'-',1,1)+1,instr(str,'-',1,2)-instr(str,'-',1,1)-1)
那在mysql里面Q可以试试这样SUBSTRING_INDEX(SUBSTRING_INDEX(str,'-',2),'-',-1),意思就是取W二?之前的str后（2005-10Q，再取倒数W一?之后的内?/p>
oracle的nvlQss,ddQ函数在mysql中怎么实现Q?
{：ifnull(ss,dd)
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