Java 使用本机查询时Hibernate 分页不起作用(命名查询存在但其结果类型不兼容)

与解决方案类似，您需要为count本机查询指定返回类型.

<?xml version="1.0" encoding="UTF-8"?>
<entity-mappings version="2.0" xmlns="http://java.sun.com/xml/ns/persistence/orm"
                 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:schemaLocation="http://java.sun.com/xml/ns/persistence/orm
        http://java.sun.com/xml/ns/persistence/orm_2_0.xsd ">

    <named-native-query name="Person.findPeople.count" result-set-mapping="cntColumnResult">
        <query>select count(*) cnt from person</query>
    </named-native-query>

    <named-native-query name="Person.findPeople">
        <query>select first_name, last_name from person</query>
    </named-native-query>

    <sql-result-set-mapping name="cntColumnResult">
        <column-result name="cnt"/>
    </sql-result-set-mapping>

</entity-mappings>

JPA version 2.1

<?xml version="1.0" encoding="UTF-8"?>
<entity-mappings version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence/orm"
                 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence/orm
    http://xmlns.jcp.org/xml/ns/persistence/orm_2_1.xsd">

    <named-native-query name="Person.findPeople.count" result-set-mapping="cntColumnResult">
        <query>select count(*) cnt from person</query>
    </named-native-query>

    <named-native-query name="Person.findPeople">
        <query>select first_name, last_name from person</query>
    </named-native-query>

    <sql-result-set-mapping name="cntColumnResult">
        <column-result name="cnt" class="java.lang.Long"/>
    </sql-result-set-mapping>

</entity-mappings>

或

<?xml version="1.0" encoding="UTF-8"?>
<entity-mappings version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence/orm"
                 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence/orm
    http://xmlns.jcp.org/xml/ns/persistence/orm_2_1.xsd">

    <named-native-query name="Person.findPeople.count" result-set-mapping="cntConstructorResult">
        <query>select count(*) cnt from person</query>
    </named-native-query>

    <named-native-query name="Person.findPeople">
        <query>select first_name, last_name from person</query>
    </named-native-query>

    <sql-result-set-mapping name="cntConstructorResult">
        <constructor-result target-class="java.lang.Long">
            <column name="cnt" class="java.lang.Long"/>
        </constructor-result>
    </sql-result-set-mapping>

</entity-mappings>

我认为这是spring-data-jpa中的一个缺陷或可能是一个新特性.Problematic source code line

countQuery = em.createNamedQuery(countQueryName, Long.class);

如果在查询创建期间不传递Long.class类型，我们将不需要在映射配置中为count查询指定确切的类型.Hibernate在这种情况下运行良好.

        Query query = getQueryMethod().isNativeQuery()
                ? em.createNativeQuery(queryString)
                : em.createQuery(queryString, Long.class);

因此，如果您有时间，请发布spring data jpa项目的新版本，这样一个小的查询更正将大大简化映射配置.