Question

由于某种原因，我无法告诉，当我尝试使用子查询从CriteriaQuery获取列表时会出现异常。有人请帮忙!!! 这是代码：

public String[] getProductsDistinctBySubQueriesName(String category) {
    CriteriaBuilder builder = em.getCriteriaBuilder();
    CriteriaQuery<Tuple> criteria = builder.createTupleQuery();
    //subquery
    Subquery<Integer> subqueries = criteria.subquery(Integer.class);
    Root<Productscategory> productCategory = subqueries.from(Productscategory.class);
    subqueries.select(productCategory.<Integer>get("productscategoryid"))
            .where(builder.equal((productCategory.<String>get("productcatgoryname")), category));
    //outerquery
    Root<Products> root = criteria.from(Products.class);
    criteria.multiselect(root.get(Products_.productname)).distinct(true)
            .where(builder.in(root.get("productscategoryid")).value(subqueries));


    List<Tuple> tupleResult = em.createQuery(criteria).getResultList(); // the exception is thrown here
    String[] arrayProducts = new String[tupleResult.size()];
    for (int i = 0; i < tupleResult.size(); i++) {
        arrayProducts[i] = (String) tupleResult.get(i).get(0);
    }
    return arrayProducts;

}

这是例外

内部异常：com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException：SQL语法中有错误;检查与您的MySQL服务器版本相对应的手册，以便在#productscategoryid附近使用正确的语法。产品类别t1 WHERE（t1.productcatgoryname =＆＃39; Pri＆＃39; at line 1 错误代码：1064 错误代码：1064 调用：SELECT DISTINCT t0.productname FROM products t0 WHERE t0.productscategoryid IN（SELECT t1.productscategoryid.t1.productscategoryid FROM productscategory t1 WHERE（t1.productcatgoryname =？）） bind =＆gt; [1参数界限] 调用：SELECT DISTINCT t0.productname FROM products t0 WHERE t0.productscategoryid IN（SELECT t1.productscategoryid.t1.productscategoryid FROM productscategory t1 WHERE（t1.productcatgoryname =？）） bind =＆gt; [1参数界限] 查询：TupleQuery（referenceClass = Products sql =＆＃34; SELECT DISTINCT t0.productname FROM products t0 WHERE t0.productscategoryid IN（SELECT t1.productscategoryid.t1.productscategoryid FROM productscategory t1 WHERE（t1.productcatgoryname =？））＆＃34 ;）查询：TupleQuery（referenceClass = Products sql =＆＃34; SELECT DISTINCT t0.productname FROM products t0 WHERE t0.productscategoryid IN（SELECT t1.productscategoryid.t1.productscategoryid FROM productscategory t1 WHERE（t1.productcatgoryname =？））＆＃34 ;） at org.eclipse.persistence.internal.jpa.QueryImpl.getDetailedException（QueryImpl.java:378） at org.eclipse.persistence.internal.jpa.QueryImpl.getDetailedException（QueryImpl.java:378）在org.eclipse.persistence.internal.jpa.QueryImpl.executeReadQuery（QueryImpl.java:260）在org.eclipse.persistence.internal.jpa.QueryImpl.getResultList（QueryImpl.java:469） at com.inventory.service.ProductsServices.getProductsDistinctBySubQueriesName（ProductsServices.java:112） at com.inventory.service.ProductsServices.getAllByName（ProductsServices.java:211） at com.inventory.server.InventorySocketRequest.getServiceClass（InventorySocketRequest.java:77）在com.inventory.server.InventorySocketRequest.run（InventorySocketRequest.java:44）引起：Exception [EclipseLink-4002]（Eclipse Persistence Services - 2.5.1.v20130918-f2b9fc5）：org.eclipse.persistence.exceptions.DatabaseException 内部异常：com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException：SQL语法中有错误;检查与您的MySQL服务器版本相对应的手册，以便在#productscategoryid附近使用正确的语法。产品类别t1 WHERE（t1.productcatgoryname =＆＃39; Pri＆＃39; at line 1 错误代码：1064 调用：SELECT DISTINCT t0.productname FROM products t0 WHERE t0.productscategoryid IN（SELECT t1.productscategoryid.t1.productscategoryid FROM productscategory t1 WHERE（t1.productcatgoryname =？）） bind =＆gt; [1参数界限] 查询：TupleQuery（referenceClass = Products sql =＆＃34; SELECT DISTINCT t0.productname FROM products t0 WHERE t0.productscategoryid IN（SELECT t1.productscategoryid.t1.productscategoryid FROM productscategory t1 WHERE（t1.productcatgoryname =？））＆＃34 ;） at org.eclipse.persistence.exceptions.DatabaseException.sqlException（DatabaseException.java：340）在org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall（DatabaseAccessor.java:682）在org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeCall（DatabaseAccessor.java:558） at org.eclipse.persistence.internal.sessions.AbstractSession.basicExecuteCall（AbstractSession.java:1991）在org.eclipse.persistence.sessions.server.ServerSession.executeCall（ServerSession.java:570）在org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall（DatasourceCallQueryMechanism.java:242）在org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall（DatasourceCallQueryMechanism.java:228）在org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeSelectCall（DatasourceCallQueryMechanism.java:299）在org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.selectAllRows（DatasourceCallQueryMechanism.java:694）在org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRowsFromTable（ExpressionQueryMechanism.java:2738）在org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllReportQueryRows（ExpressionQueryMechanism.java:2675）在org.eclipse.persistence.queries.ReportQuery.executeDatabaseQuery（ReportQuery.java:848）在org.eclipse.persistence.queries.DatabaseQuery.execute（DatabaseQuery.java:899） at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute（ObjectLevelReadQuery.java:1127）在org.eclipse.persistence.queries.ReadAllQuery.execute（ReadAllQuery.java:403） at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeInUnitOfWork（ObjectLevelReadQuery.java:1215） at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.internalExecuteQuery（UnitOfWorkImpl.java:2896） at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery（AbstractSession.java:1793） at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery（AbstractSession.java:1775）在org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery（AbstractSession.java:1740）在org.eclipse.persistence.internal.jpa.QueryImpl.executeReadQuery（QueryImpl.java:258） ......还有5个引发者：com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException：您的SQL语法中有错误;检查与您的MySQL服务器版本相对应的手册，以便在#productscategoryid附近使用正确的语法。产品类别t1 WHERE（t1.productcatgoryname =＆＃39; Pri＆＃39; at line 1 at sun.reflect.NativeConstructorAccessorImpl.newInstance0（Native Method） at sun.reflect.NativeConstructorAccessorImpl.newInstance（NativeConstructorAccessorImpl.java:57） at sun.reflect.DelegatingConstructorAccessorImpl.newInstance（DelegatingConstructorAccessorImpl.java:45）在java.lang.reflect.Constructor.newInstance（Constructor.java:525）在com.mysql.jdbc.Util.handleNewInstance（Util.java:411）在com.mysql.jdbc.Util.getInstance（Util.java:386）在com.mysql.jdbc.SQLError.createSQLException（SQLError.java:1053）在com.mysql.jdbc.MysqlIO.checkErrorPacket（MysqlIO.java:4120）在com.mysql.jdbc.MysqlIO.checkErrorPacket（MysqlIO.java:4052）在com.mysql.jdbc.MysqlIO.sendCommand（MysqlIO.java:2503）在com.mysql.jdbc.MysqlIO.sqlQueryDirect（MysqlIO.java:2664）在com.mysql.jdbc.ConnectionImpl.execSQL（ConnectionImpl.java:2794）在com.mysql.jdbc.PreparedStatement.executeInternal（PreparedStatement.java:2155）在com.mysql.jdbc.PreparedStatement.executeQuery（PreparedStatement.java:2322）在org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeSelect（DatabaseAccessor.java:1007）在org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall（DatabaseAccessor.java:642） ......还有24个

Answer 1

尝试使用此查询而不是您的查询，这与EclipseLink提供程序完美配合，不确定您的查询在eclipselink中不起作用但在hibernate中工作，我测试了下面的查询，您将能够选择基于ProductCategoryName。

    EntityManagerFactory emf = Persistence.createEntityManagerFactory("jpaQuery");
    EntityManager em = emf.createEntityManager();

    String category = "cat2";

    CriteriaBuilder builder = em.getCriteriaBuilder();

    CriteriaQuery<Products> query = builder.createQuery(Products.class);
    Root<Products> products = query.from(Products.class);

    Subquery<Productscategory> squery = query.subquery(Productscategory.class);
    Root<Productscategory> productCategoryRoot = squery.from(Productscategory.class);
    Join<Productscategory, Products> join = productCategoryRoot.join("productsCollection");

    squery.select(productCategoryRoot)
    .where(builder.equal(join, products), builder.equal(productCategoryRoot.get("productcatgoryname"), category));

    query.where( builder.exists(squery));
    List<Products> productList = em.createQuery(query).getResultList(); 

    for (Products product : productList) {
           System.out.println(product);
    }

在哪个类别中是您要搜索的类别的名称..

这解决了问题=）..如果这样做，不要忘记接受答案XD。

从CriteriaQuery获取列表的例外情况

1 个答案: