尝试将 SQL 查询转换为 JPA 查询

Question

我想将此 sql 查询转换为 JPA 查询，但我似乎无法理解它...我应该使用 findByMarinaIdAndMovementGroupMeanId 吗？或 findByMarinaIdAndMovementGroupMeanIdAndMovementMeanId??

Sql:

 select m.* from movement_group m
    join movement_group_mean mgm on m.id = mgm.movement_group_id
    join movement_mean mm on mgm.movement_mean_id = mm.id
where mm.id = 1 and m.marina_id = :marinaId and mm.active = true;

运动组：

@Entity
public class MovementGroup {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
    private String name;
    private String code;
    private LocalDateTime createdAt;
    private LocalDateTime updatedAt;
    private Boolean active;
    private String iconUrl;
    
    
    @OneToMany(mappedBy = "movementGroup")
    private Set<MovementGroupMean> movementGroupMeans;
    
    @JsonIgnore
    @ManyToOne()
    @JoinColumn(name = "marina_id")
    private Marina marina;

MovementGroupMean:

@Entity
public class MovementGroupMean {

    @EmbeddedId
    @JsonIgnore
    private MovementGroupMeanPK movementGroupMeanPK;

    @JsonBackReference
    @ManyToOne
    @JoinColumn(name = "movement_group_id", insertable = false, updatable = false)
    private MovementGroup movementGroup;
    
    @ManyToOne
    @JoinColumn(name = "movement_mean_id", insertable = false, updatable = false)
    private MovementMean movementMean;

运动平均值：

@Entity
public class MovementMean {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
    private String name;
    @Enumerated(EnumType.STRING)
    private MovementMeanType movementMeanType;
    private Boolean active;
    private LocalDateTime createdAt;
    private LocalDateTime updatedAt;
    
    @JsonBackReference
    @ManyToOne()
    @JoinColumn(name = "marina_id")
    private Marina marina;

Answer 1

不确定问题出在哪里，所以请原谅SQL->JPQL:

上的冗长解释

用您的实体名称替换您的 table 名称
- movement_group -> 运动组
将您的联接替换为 java 引用，让 JPA 使用您定义的关系映射。
- “在 m.id = mgm.movement_group_id 上加入 movement_group_mean mgm”变为“加入 m.movementGroupMeans mgm”
- "join movement_mean mm on mgm.movement_mean_id = mm.id 变为 "join mgm.movementMean mm"

唯一棘手的地方是您的实体没有为 marina_id 值定义基本映射。因此，要获得 m.marina_id，您必须使用 'marina' 引用并使用其可能的 ID 值： "m.marina_id = :marinaId" -> "m.marina.id = :marinaId"

给你 JPQL：

"Select m from MovementGroup m join m.movementGroupMeans mgm join mgm.movementMean mm where mm.id = 1 and m.marina.id = :marinaId and mm.active = true"

尝试将 SQL 查询转换为 JPA 查询

Trying to Convert a SQL Query to a JPA Query

jpa

spring-boot