数据库常见的join方式有三种：inner join, left outter join, right outter join(还有一种full join，因不常用，本文不讨论)。这三种连接方式都是将两个以上的表通过on条件语句，拼成一个大表。以下是它们的共同点：
1. 关于左右表的概念。左表指的是在SQL语句中排在left join左边的表，右表指的是排在left join右边的表。
2. 在拼成的大表中，左表排在左边，右表排在右边。
3. on条件语句最好用=号对两表相应的主外键进行连接。当然，也可以用其他操作符，如>, <, 来连接两表的任一字段，此时的关系将非常复杂，连接后的记录数也随之而变得不确定。如果在一些特殊的场合中需要用到这种方式，必须通过简单的实例加以确认，否则，连接结果很可能不是我们所想要的！
4. on条件语句不能省略。
5. 可以连锁使用join，每次使用join都令另一表与当前的表或连接的结果相连接。
在下文中，用到了两个表，"部门"表与"组织"表，其中，"部门"表有一名为"组织编号"的外键，指向"组织"表中的主键"编号"。
inner join
格式：select * from 部门 inner join 组织 on 部门.组织编号 = 组织.编号
目的：将两表中符合on条件的所有记录都找出来。
规律：
1. 拼出的大表记录不会增加。
2. 如果左边与右表的关系是一对多的关系，在选出的任一记录中，假若右表有多个记录与其对应，那么，连接后的左表，主键将不再唯一。
典型应用：将存在多关系的引用表放在左表，将存在一关系的被引用表放在右表，通过=号将主外键进行连接，通过对右表设定过滤条件，选出相应的且主键唯一的左表记录。
备注：inner join 是默认的连接方式，可缩写为join。
转化为where子句：
select * from 部门, 组织 where 部门.组织编号 = 组织.编号
left outter join
格式: select * from 部门 left join 组织 on 部门.组织编号 = 组织.编号
格式: select * from 组织 left join 部门 on 组织.编号 = 部门.组织编号
目的：将左表的所有记录列出，右表中只要符合on条件的，与左表记录相拼合，不符合条件的，填以null值。
规律：
1. 选出所有符合条件的左表，如果左边与右表的关系是一对一的关系，则拼成的大表记录不会改变。
如果左边与右表的关系是多对一的关系，则拼成的大表记录也不会改变。
如果左边与右表的关系是一对多的关系，则拼成的大表记录会增加。对于每一具有一对多关系的左表记录，如果左表1：N与右表对应，那么会多出N-1条记录。例如，如果左表第一条记录1：3对应于右表，多出2条记录。如果左表第二条记录1：2对应于右表，则再多出1条记录。这样，总共多出3条记录。其他类推。
2. 如果左边与右表的关系是一对多的关系，在选出的任一记录中，假若右表有多个记录与其对应，那么，连接后的左表，主键将不再唯一。
3. 如果左边与右表的关系是一对多的关系，对于左表任一记录，如果右表没有记录与其相对应，则全部填以null值。
典型应用：将存在多关系的引用表放在左表，将存在一关系的被引用表放在右表，通过对右表设定过滤条件，选出相应的且主键唯一的左表记录。
备注：left outter join可用left join代替。在有些数据库中，如HSqlDb, 只能使用left join而不能使用left outter join。
转化为where子句：
select * from 部门, 组织 where 部门.组织编号 = 组织.编号
right outter join
格式: select * from 部门 right join 组织 on 部门.组织编号 = 组织.编号
格式: select * from 组织 right join 部门 on 部门.组织编号 = 组织.编号
目的：将右表的所有记录列出，左表中只要符合on条件的，与右表记录相拼合，不符合条件的，填以null值。
规律：(与left outter join相反)
典型应用：可转化成left outter join。例如
select * from 组织 right join 部门 on 部门.组织编号 = 组织.编号
与
select * from 部门 left join 组织 on 部门.组织编号 = 组织.编号
的效果一样
备注：right outter join可用right join代替。在有些数据库中，如HSqlDb, 没有实现right join功能。
转化为where子句：
select * from 部门, 组织 where 部门.组织编号 = 组织.编号
Session Descriptions
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Expect real-life examples and code-snippets.
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(JBI) specification. ServiceMix provides business integration capabilities using a complete JBI container and a host of JBI components including those for orchestration, rules, scheduling, transformation, validation and JBI transports including those for email, file, FTP, HTTP, JMS, RSS, VFS, VM and many more.
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This talk introduces XQuery to the Java developer. I'll explain the XQuery language; I'll show how to call XQuery from Java (including coverage of JSR-225, the XQuery API for Java); and I'll show the XQuery and Java code behind a sample custom book publishing application.
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BOFs
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Jonas Bonér and Patrick Calahan, Terracotta
Clustering and other forms of distributed computing are not easy in Java. The proliferation of clustered caches in the market today illustrates the need for tools to make clustering in Java easier. The problems with most current solutions are that they break Java's natural programming model – with unnatural API's and breaking fundamental object identity. This Birds of a Feather session will focus on the importance of preserving object identity in a cluster, and will illustrate a runtime system that understands the developer's domain objects and clusters objects across a cluster transparently while maintaining object identity, using detailed code examples to illustrate the concepts.