Как создать внутренний HQL

Question

Я пытаюсь запросить данные из вспомогательного запроса с использованием HQL. У меня есть 2 классов:

Supplier.java:

@Entity 
@Table(name = "Suppliers") 
public class Supplier implements Serializable { 

@Id 
String id; 
String name; 

@ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL) 
@JoinTable(name = "Suppliers_Categories", joinColumns = { @JoinColumn(name = "SupplierId") }, inverseJoinColumns = { @JoinColumn(name = "CategoryId") }) 
Set<Category> categories = new HashSet<Category>(); 

@OneToMany(mappedBy = "supplier") 
Collection<Product> products; 

public Set<Category> getCategories() { 
    return this.categories; 
} 

public void setCategories(Set<Category> categories) { 
    this.categories = categories; 
} 

public String getId() { 
    return id; 
} 

public void setId(String id) { 
    this.id = id; 
} 

public String getName() { 
    return name; 
} 

public void setName(String name) { 
    this.name = name; 
} 

public Collection<Product> getProducts() { 
    return products; 
} 

public void setProducts(Collection<Product> products) { 
    this.products = products; 
} 
} 

Category.java:

@Entity 
@Table(name = "Categories") 
public class Category implements Serializable { 
@Id 
@GeneratedValue 
Integer id; 
String name; 
String namevn; 

@ManyToMany(mappedBy = "categories") 
Set<Supplier> suppliers = new HashSet<Supplier>(0); 

@OneToMany(mappedBy = "category") 
Collection<Product> products; 

@OneToOne 
@JoinColumn(name = "ProductFeature") 
Product featureProduct; 

public Set<Supplier> getSuppliers() { 
    return this.suppliers; 
} 

public Product getFeatureProduct() { 
    return featureProduct; 
} 

public void setFeatureProduct(Product featureProduct) { 
    this.featureProduct = featureProduct; 
} 

public String getNamevn() { 
    return namevn; 
} 

public void setNamevn(String namevn) { 
    this.namevn = namevn; 
} 

public void setSuppliers(Set<Supplier> suppliers) { 
    this.suppliers = suppliers; 
} 

public int getId() { 
    return id; 
} 

public void setId(int id) { 
    this.id = id; 
} 

public String getName() { 
    return name; 
} 

public void setName(String name) { 
    this.name = name; 
} 

public Collection<Product> getProducts() { 
    return products; 
} 

public void setProducts(Collection<Product> products) { 
    this.products = products; 
} 
} 

Что мне нужно, это выбрать "supplier.id" в категории, которая имеет идентификатор = 1. Мой запрос:

SELECT id FROM Поставщик as s где s in (SELECT поставщиков FROM Категория как c WHERE c.id = 1)

Но есть некоторые ошибки:

Exception in thread "main" org.hibernate.exception.SQLGrammarException: could not execute query 
    at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:90) 
    at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66) 
    at org.hibernate.loader.Loader.doList(Loader.java:2231) 
    at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125) 
    at org.hibernate.loader.Loader.list(Loader.java:2120) 
    at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:401) 
    at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:361) 
    at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196) 
    at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1148) 
    at org.hibernate.impl.QueryImpl.list(QueryImpl.java:102) 
    at eshop.util.XHibernate.list(XHibernate.java:85) 
    at eshop.util.XHibernate.main(XHibernate.java:91) 
Caused by: com.microsoft.sqlserver.jdbc.SQLServerException: Incorrect syntax near '-'. 
    at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDatabaseError(SQLServerException.java:196) 
    at com.microsoft.sqlserver.jdbc.SQLServerStatement.getNextResult(SQLServerStatement.java:1458) 
    at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement.doExecutePreparedStatement(SQLServerPreparedStatement.java:388) 
    at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement$PrepStmtExecCmd.doExecute(SQLServerPreparedStatement.java:338) 
    at com.microsoft.sqlserver.jdbc.TDSCommand.execute(IOBuffer.java:4016) 
    at com.microsoft.sqlserver.jdbc.SQLServerConnection.executeCommand(SQLServerConnection.java:1414) 
    at com.microsoft.sqlserver.jdbc.SQLServerStatement.executeCommand(SQLServerStatement.java:176) 
    at com.microsoft.sqlserver.jdbc.SQLServerStatement.executeStatement(SQLServerStatement.java:151) 
    at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement.executeQuery(SQLServerPreparedStatement.java:281) 
    at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208) 
    at org.hibernate.loader.Loader.getResultSet(Loader.java:1808) 
    at org.hibernate.loader.Loader.doQuery(Loader.java:697) 
    at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259) 
    at org.hibernate.loader.Loader.doList(Loader.java:2228) 
    ... 9 more 

Есть ли способ запроса в моей идее с использованием 1 HQL? Любая помощь будет большой.

Answer 1

Вам нужно узнать о соединениях. Все, что вам нужно, это

select s.id from Supplier s 
join s.categories c 
where c.id = :categoryId