我是jpa中的初学者,我遇到了复合查询。 然后我开始搜索解决方案。许多人建议使用标准API。
所以问题是:如何使用criteriaQuery创建类似的查询?
MySQL版
SELECT role FROM Role WHERE id_role=(SELECT id_role FROM Client WHERE email=:email)
角色
@Entity
@Table(name="role")
public class Role {
@Id
public int id_role;
private enum enumRole {ADMIN, CLIENT}
@Column(name="role")
private enumRole role;
public Role() {
}
public Role(enumRole role) {
this.role = role;
}
public String getRole() {
return this.role.name();
}
public void setRole(String role) {
this.role = enumRole.valueOf(role);
}
@OneToMany(targetEntity = Client.class)
private List clientList;
}
客户端
@Entity
@Table(name ="client")
public class Client {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
public Long Id;
@Column(name="first_name", length = 25)
private String firstName;
@Column(name="surname", length = 25)
private String surName;
@Column(name="password", length = 30)
private String password;
@Column(name="email")
private String email;
@Column(name="username", length = 15)
private String username;
public Client() {
}
@ManyToMany(targetEntity = Ticket.class)
private Set ticketSet;
public Client(String firstName, String surName, String password, String email, String username) {
this.firstName = firstName;
this.surName = surName;
this.password = password;
this.email = email;
this.username = username;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getSurName() {
return surName;
}
public void setSurName(String surName) {
this.surName = surName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
}
}
答案 0 :(得分:0)
您是否可以在客户端和角色之间创建映射?是@OneToMany还是@ManyToMany?如果是这样,那么你不需要编写任何sql,并且可以使用简单的JPA查询方法http://docs.spring.io/spring-data/jpa/docs/current/reference/html/#repositories.query-methods.query-creation