英文:
Entity Graph does not work in Entity Layer but work in Repository Layer
问题
我有一个实体链 User -> CryptoWallet -> List<CryptoCount>
```javapublic class User {@Id@Column(name = "id")@GenericGenerator(name = "uuidFromIp" , strategy = "org.hibernate.id.uuid.CustomVersionOneStrategy")@GeneratedValue(generator = "uuid_gen_strategy")private UUID id;@Column(name = "user_name")private String userName;@Column(name = "email")private String email;@OneToOne(cascade = CascadeType.ALL)@JoinColumn(name = "crypto_wallet_id")private CryptoWallet cryptoWallet;}```
```javapublic class CryptoWallet {@Id@Column(name = "id")@GeneratedValue(strategy = GenerationType.IDENTITY)private Long id;@Column(name = "balance")private BigDecimal balance;@OneToMany(mappedBy = "cryptoWallet", cascade = CascadeType.ALL)private List<CryptoCount> cryptoCounts;@OneToOne(mappedBy = "cryptoWallet")private User walletOwner;}```
```javapublic class CryptoCount {@Id@Column(name = "id")@GeneratedValue(strategy = GenerationType.IDENTITY)private Long id;@ManyToOne@JoinColumn(name = "crypto_id")private CryptoCurrency cryptoCurrency;@Column(name = "count")private BigDecimal countOfCrypto;@ManyToOne@JoinColumn(name = "crypto_wallet_id")private CryptoWallet cryptoWallet;}```
我的任务是以一次请求加载 CryptoWalletOwnerId 所有的 CryptoCount
当我在 Repository 层使用以下方法时，一切都正常工作（只有一个查询）。
@EntityGraph(attributePaths = {"cryptoCurrency","cryptoWallet","cryptoWallet.walletOwner"})List<CryptoCount> findAllByCryptoWalletWalletOwnerId(UUID id);
但是
当我像这样注释 CryptoCount：
@NamedEntityGraph(name = "CryptoCountWithCurrencyAndWallet",attributeNodes = {@NamedAttributeNode(value = "cryptoCurrency"),@NamedAttributeNode(value = "cryptoWallet")})
以及像这样注释 CryptoWallet：
@NamedEntityGraph(name = "WalletWithCryptoCountsAndWalletOwner", attributeNodes = {@NamedAttributeNode(value = "cryptoCounts"),@NamedAttributeNode(value = "walletOwner",subgraph = "UserWithWallet")}, subgraphs = {@NamedSubgraph(name = "UserWithWallet", attributeNodes = @NamedAttributeNode("cryptoWallet"))})
还有像这样注释 User：
@NamedEntityGraph(name = "UserWithWallet",attributeNodes = {@NamedAttributeNode("cryptoWallet")},subgraphs = {@NamedSubgraph(name = "userWithWallet", attributeNodes = {@NamedAttributeNode("cryptoWallet")})})
并且在 Repository 中使用以下方法：
@EntityGraph(value = "CryptoCountWithCurrencyAndWallet")List<CryptoCount> findAllByCryptoWalletWalletOwnerId(UUID id);
我会得到两个数据库查询，而不是一个。我的代码有什么问题？
英文:
I have a chain of entities User -> CryptoWallet -> List<CryptoCount>
public class User {@Id@Column(name = "id")@GenericGenerator(name = "uuidFromIp" , strategy = "org.hibernate.id.uuid.CustomVersionOneStrategy")@GeneratedValue(generator = "uuid_gen_strategy")private UUID id;@Column(name = "user_name")private String userName;@Column(name = "email")private String email;@OneToOne(cascade = CascadeType.ALL)@JoinColumn(name = "crypto_wallet_id")private CryptoWallet cryptoWallet;}
2.
public class CryptoWallet {@Id@Column(name = "id")@GeneratedValue(strategy = GenerationType.IDENTITY)private Long id;@Column(name = "balance")private BigDecimal balance;@OneToMany(mappedBy = "cryptoWallet", cascade = CascadeType.ALL)private List<CryptoCount> cryptoCounts;@OneToOne(mappedBy = "cryptoWallet")private User walletOwner;}
3.
public class CryptoCount {@Id@Column(name = "id")@GeneratedValue(strategy = GenerationType.IDENTITY)private Long id;@ManyToOne@JoinColumn(name = "crypto_id")private CryptoCurrency cryptoCurrency;@Column(name = "count")private BigDecimal countOfCrypto;@ManyToOne@JoinColumn(name = "crypto_wallet_id")private CryptoWallet cryptoWallet;}
My task is to load All CryptoCount By CryptoWalletOwnerId in one request
When i use next method in Repository Layer everything work correctly(with one query).
@EntityGraph(attributePaths = {"cryptoCurrency","cryptoWallet","cryptoWallet.walletOwner"})List<CryptoCount> findAllByCryptoWalletWalletOwnerId(UUID id);
BUT
When I annotate CryptoCount like this:
@NamedEntityGraph(name = "CryptoCountWithCurrencyAndWallet",attributeNodes = {@NamedAttributeNode(value = "cryptoCurrency"),@NamedAttributeNode(value = "cryptoWallet")})
And CryptoWallet like this:
@NamedEntityGraph(name = "WalletWithCryptoCountsAndWalletOwner", attributeNodes = {@NamedAttributeNode(value = "cryptoCounts"),@NamedAttributeNode(value = "walletOwner",subgraph = "UserWithWallet")}, subgraphs = {@NamedSubgraph(name = "UserWithWallet", attributeNodes = @NamedAttributeNode("cryptoWallet"))})
And also User like this:
@NamedEntityGraph(name = "UserWithWallet",attributeNodes = {@NamedAttributeNode("cryptoWallet")},subgraphs = {@NamedSubgraph(name = "userWithWallet", attributeNodes = {@NamedAttributeNode("cryptoWallet")})})
And also use next method in Repository:
@EntityGraph(value = "CryptoCountWithCurrencyAndWallet")List<CryptoCount> findAllByCryptoWalletWalletOwnerId(UUID id);
I get two database queries instead of one. Whats wrong with my code?
答案1
得分: 0
@NamedEntityGraph(name = "CryptoCountWithCurrencyAndWallet", attributeNodes = {
@NamedAttributeNode(value = "cryptoCurrency"),
@NamedAttributeNode(value = "cryptoWallet", subgraph = "withWalletOwner")
}, subgraphs = {
@NamedSubgraph(name = "withWalletOwner", attributeNodes = {@NamedAttributeNode("walletOwner")})
})
在 CryptoCount 中解决了这个问题。
英文:
@NamedEntityGraph(name = "CryptoCountWithCurrencyAndWallet",attributeNodes = {@NamedAttributeNode(value = "cryptoCurrency"),@NamedAttributeNode(value = "cryptoWallet",subgraph = "withWalletOwner")},subgraphs = {@NamedSubgraph(name = "withWalletOwner",attributeNodes = {@NamedAttributeNode("walletOwner")})})
In CryptoCount solved the problem
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