<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[ZHEngineer的专栏]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/ZHEngineer</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; ZHEngineer]]></copyright><item><title><![CDATA[Oracle的多个join的区别]]></title><link>https://blog.youkuaiyun.com/ZHEngineer/article/details/8911425</link><guid>https://blog.youkuaiyun.com/ZHEngineer/article/details/8911425</guid><author>ZHEngineer</author><pubDate>Fri, 10 May 2013 16:10:15 +0800</pubDate><description><![CDATA[1.栏位合并
left join、right join、inner join、full join
left join(左联接)： 返回包括左表中的所有记录和右表中联结字段相等的记录 
right join(右联接)： 返回包括右表中的所有记录和左表中联结字段相等的记录
inner join(等值连接)： 只返回两个表中联结字段相等的行
FULL JOIN ：关键字会从左表 (Person]]></description><category></category></item><item><title><![CDATA[Record change by another]]></title><link>https://blog.youkuaiyun.com/ZHEngineer/article/details/5030733</link><guid>https://blog.youkuaiyun.com/ZHEngineer/article/details/5030733</guid><author>ZHEngineer</author><pubDate>Fri, 18 Dec 2009 11:51:00 +0800</pubDate><description><![CDATA[1.TClientDataSet的Applyupdate提交时，报“Record change by another”的原因之一，客户端字段类型FieldBCD的改成FieldFloat，相应的数据表字段从Integer或Number修改成Float类型； 2.TClientDataSet的IndexFieldNames设置为空，不然保存后记录会跳动；3.TdataSetProvide]]></description><category></category></item><item><title><![CDATA[1.关联语句inner join on 和 left join on的区别]]></title><link>https://blog.youkuaiyun.com/ZHEngineer/article/details/5030660</link><guid>https://blog.youkuaiyun.com/ZHEngineer/article/details/5030660</guid><author>ZHEngineer</author><pubDate>Fri, 18 Dec 2009 11:43:00 +0800</pubDate><description><![CDATA[1.关联语句inner join on 和 left join on的区别inner join on相当于以下语句select a.*,b.* from user a ,UserChannel b where a.UserID=B.UserID 即和select a.*,b.* from user a inner join UserChannel b on a.userid=b.UserID结]]></description><category></category></item></channel></rss>