java - 如何在 Hibernate 的多列索引中指定列的顺序？

Question

我正在创建一个多列索引，如下所示:

@Entity
public class Ranking extends Model {
    @ManyToOne
    @Index(name = "ranking_ix")
    public Rankable rankable;

    @ManyToOne
    @Index(name = "ranking_ix")
    public Criteria criteria;

    @Index(name = "ranking_ix")
    public double rank;
}

但是我看不到如何控制三列在复合索引中的出现顺序(这可能是确保最佳查询性能所必需的)。如何实现？

Answer 1

这可以用 org.hibernate.annotations.Table 注释指定，​​除了 javax.persistence.Table 注释外还使用它:

@Entity
@javax.persistence.Table(name="Ranking")
@org.hibernate.annotations.Table(
    appliesTo="Ranking",
    indexes = { @Index(name="ranking_ix", columnNames = { "rankable", "criteria", "rank" } ) }
)
public class Ranking extends Model {
    @ManyToOne
    public Rankable rankable;

    @ManyToOne
    public Criteria criteria;

    @Index(name = "ranking_ix")
    public double rank;
}