1、一对一 (One to One)
共三种情况:
1.1 主键共享
1.2
外键共享
1.3 中间表关联
1.1 code:
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@Entitypublic class article { @Id @GeneratedValue public
Integer getArticleId() { return
articleId; } ..... @OneToOne(cascade=CascadeType.ALL) @PrimaryKeyJoinColumn public
articleContent getContent() { return
content; } ......} |
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@Entitypublic class articleContent { @Id @GeneratedValue public
Integer getcId() { return
cId; } ....} |
执行保存 生成两张无外键的独立表
1.2 code:
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@Entitypublic class article { @OneToOne(cascade=CascadeType.ALL) @JoinColumn(name="cid_fk") public
articleContent getContent() { return
content; } }@Entitypublic
class articleContent { @OneToOne(mappedBy="articleContent") public
article ArticleEntity;} |
执行保存，生成两张表，同时article生成一个cid_fk字段 关联 articleContent主键ID
1.3 code:
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@Entitypublic class article { @Id @GeneratedValue public
Integer getArticleId() { return
articleId; } @OneToOne(cascade=CascadeType.ALL) @JoinTable(name="article_content", joinColumns=@JoinColumn(name="aid"), inverseJoinColumns=@JoinColumn(name="aid_fk")) public
articleContent getContent() { return
content; } ......} |
生成三张表 分别为：article，article_content，articlecontent 其中 article_content 分别生成两个外键具体参考等价建表语句：
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CREATE TABLE `article_content` ( `aid_fk` int(11) DEFAULT
NULL, `aid` int(11) NOT
NULL, PRIMARY
KEY (`aid`), KEY
`FK_7pgn2vn8r1lpswmh5v2ix667s` (`aid_fk`), CONSTRAINT
`FK_ebfc4cs1sishg6u8kwpvgqqj9` FOREIGN
KEY (`aid`) REFERENCES
`article` (`articleId`), CONSTRAINT
`FK_7pgn2vn8r1lpswmh5v2ix667s` FOREIGN
KEY (`aid_fk`) REFERENCES
`articlecontent` (`cId`)) ENGINE=InnoDB DEFAULT
CHARSET=utf8; |
Rhythmk 学习 Hibernate 08 - Hibernate annotation 关联关系注解,布布扣,bubuko.com
Rhythmk 学习 Hibernate 08 - Hibernate annotation 关联关系注解
原文：http://www.cnblogs.com/rhythmK/p/3705259.html