[펌] Hibernate Criteria on Multiple Tables

http://kruders.com/hibernate/hibernate-criteria-on-multiple-tables/#comment-9371

Hibernate Criteria JOIN API allows users to perform join operation. Suppose you have two tables Club and Team. The relational model is shown below in Figure 25.1

 

Figure 25.1

Club table contains data as shown in Figure 25.2

Figure 25.2

Team table contains data as shown in Figure 25.3

Figure 25.3

Suppose you have to perform a operation like

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select club.clubid, club.name, team.clubid, team.teamid, team.teamname from Club club, Team team where club.clubid=team.clubid;

Then you can write this statement using Criteria in a very simple way

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Criteria criteria = session.createCriteria(Club.class);     criteria.setFetchMode("Team", FetchMode.JOIN);     List list = criteria.list();

Now Suppose you have to apply restriction on join operation such as

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select club.clubid, club.name, team.clubid, team.teamid, team.teamname from Club club, Team team where club.clubid=team.clubid and club.name='Arsenal' and team.teamname='Team A';

Then you can write the above statement in criteria as

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Criteria criteria = session.createCriteria(Club.class,"club")     .createAlias("club.team","team")     .add(Restrictions.eq("club.name", "Arsenal"))     .add(Restrictions.eq("team.teamname", "Team A"));     List list = criteria.list();

Sql Script for Sample Code given below

Use the following Sql Script for creating table and inserting record.

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CREATE TABLE club (   clubId INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,   name VARCHAR(20) NOT NULL,   PRIMARY KEY (ClubId) );     CREATE TABLE  team (   teamid INT(10) UNSIGNED NOT NULL,   clubid INT(10) UNSIGNED NOT NULL,   teamname VARCHAR(10) NOT NULL,   PRIMARY KEY (teamid, clubid),   FOREIGN KEY (clubid) REFERENCES club (clubid)); insert into club values(1,'Arsenal'); insert into team values(1,1,'Team A');

You can download the source code of this example here.