java - 玩!框架: using find() model method on a collection

Question

让我们假设一个具有这些字段的用户类:

@Entity
public class User extends Model {
    public String email;
    public String password;
    @ElementCollection
    public List<String> stringList;
}

我正在寻找一种方法来执行数据库请求以查找所有在其 stringList 中具有给定字符串的用户，例如

List<User> usersHelloWorld = User.find("byStringList", "HelloWorld").fetch();

当然，这是行不通的。有什么办法让它发挥作用吗？

编辑:

这是我实际的类字段:

@Entity
public class User extends Model {
    public String email;
    public String password;
    public String firstname;
    public String lastname;
    public String gender;
    public String fbId;
    public String googleId;
    @ElementCollection
    public List<String> eventTopicIds;
    @Transient
    UserEventBuffer eventBuffer;
    @Transient
    public String fbAccessToken;
    public String googleAccessToken;
}

有了这个请求:

List<User> u = User.find("SELECT u from User u where ? IN u.eventTopicIds", "internalns_rootTopic1").fetch();

我得到了那个错误:

JPAQueryException occured : Error while executing query SELECT u from User u where ? IN u.eventTopicIds: Syntax error in SQL statement "SELECT USER0_.ID AS ID3_, USER0_.EMAIL AS EMAIL3_, USER0_.FBID AS FBID3_, USER0_.FIRSTNAME AS FIRSTNAME3_, USER0_.GENDER AS GENDER3_, USER0_.GOOGLEACCESSTOKEN AS GOOGLEAC6_3_, USER0_.GOOGLEID AS GOOGLEID3_, USER0_.LASTNAME AS LASTNAME3_, USER0_.PASSWORD AS PASSWORD3_ FROM USER USER0_ CROSS JOIN USER_EVENTTOPICIDS EVENTTOPIC1_ WHERE USER0_.ID=EVENTTOPIC1_.USER_ID AND (? IN (.[*])) "; expected "NOT, EXISTS, SELECT, FROM"; SQL statement: select user0_.id as id3_, user0_.email as email3_, user0_.fbId as fbId3_, user0_.firstname as firstname3_, user0_.gender as gender3_, user0_.googleAccessToken as googleAc6_3_, user0_.googleId as googleId3_, user0_.lastname as lastname3_, user0_.password as password3_ from User user0_ cross join User_eventTopicIds eventtopic1_ where user0_.id=eventtopic1_.User_id and (? in (.)) [42001-149]

Answer 1

通常你应该能够像这样运行一个 JPA 查询

User.find("Select u from User as u inner join u.stringList as strings where ? in strings", "HelloWorld").fetch();

做了一个小测试，我的对象有电子邮件而不是字符串，但应该是一样的，除非你遇到一些保留字。问题不在于 in 关键字，我必须在内部加入 stringList 才能使用 in 关键字。之前的标记有点快:)

希望这对您有所帮助。