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&lt;a href="http://php.11519.net/5jblog"&gt;java开发技术网&lt;/a&gt;</description><language>zh-cn</language><lastBuildDate>Fri, 20 Aug 2010 10:27:02 GMT</lastBuildDate><pubDate>Fri, 20 Aug 2010 10:27:02 GMT</pubDate><ttl>60</ttl><item><title>mysql字符串函数使用笔记</title><link>http://www.blogjava.net/pdw2009/archive/2009/05/19/271603.html</link><dc:creator>有猫相伴的日子</dc:creator><author>有猫相伴的日子</author><pubDate>Tue, 19 May 2009 14:50:00 GMT</pubDate><guid>http://www.blogjava.net/pdw2009/archive/2009/05/19/271603.html</guid><wfw:comment>http://www.blogjava.net/pdw2009/comments/271603.html</wfw:comment><comments>http://www.blogjava.net/pdw2009/archive/2009/05/19/271603.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.blogjava.net/pdw2009/comments/commentRss/271603.html</wfw:commentRss><trackback:ping>http://www.blogjava.net/pdw2009/services/trackbacks/271603.html</trackback:ping><description><![CDATA[<br />
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最近要开始使用MySQL记点笔记。<br />
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select left("http://www.webmasterclub.org/&amp;id=1310",instr("http://www.webmasterclub.org/&amp;id=1310",'&amp;')-1 )<br />
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left函数，返回左边特定长度的字符串函数。<br />
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instr(str,substr)返回substr字符串在str字符串中的位置。<br />
<dt><code><font face="新宋体"><strong>LOCATE(substr,str)</strong></font></code> locate也是返回字符串的位置，但locate函数，子字符串在前面。<br />
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substring(str,2,9)，返回str字符串中从第2个位置开始的9个字符。用法与mid相同<br />
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insert(str,startpos,len,substr) 字符串替换函数，把str字符串startpos开始，len结束的字符串用substr替换
<dt><br />
select replace ('aaBBC','aB',"PPPPPP") 字符串规换
<dt><br />
注意：mysql处理字符位置时是以1为序列启始。<br />
</dt><img src ="http://www.blogjava.net/pdw2009/aggbug/271603.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.blogjava.net/pdw2009/" target="_blank">有猫相伴的日子</a> 2009-05-19 22:50 <a href="http://www.blogjava.net/pdw2009/archive/2009/05/19/271603.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item></channel></rss>