如何使用参数动态查询（原生查询）答案

【问题标题】：How to use dynamic query by parameter (native query)如何使用参数动态查询（原生查询）
【发布时间】：2021-12-05 06:38:16
【问题描述】：

下面的代码是我的存储库的一部分。静态函数不能如下使用，但是我想根据服务接管的参数值接收不同的查询。你能帮我个忙吗？提前谢谢你。

    @Query(value = " select * " +
            "from t_user usr " +
            "left outer join t_sale_order ord on usr.id = ord.user_idx " +
            "LEFT OUTER JOIN ( " +
                "SELECT " +
                    "sale_order_idx, sum(taxable_amount) + sum(non_taxable_amount) as amount " +
                "FROM t_sale_receipt " +
                "GROUP BY sale_order_idx " +
            ") receipt " +
            "ON receipt.sale_order_idx = ord.id " +
            "where NOT exists ( " +
                "select 1 from t_encourage_sent_list sl " +
                "where sl.user_idx  = usr.id and sl.push_idx = ?1 " +
            ") " +
            "AND NOT EXISTS ( SELECT 1 FROM t_user_study us WHERE us.user_idx = usr.id ) " +
//            readBookCondition(readBook) +
            "AND usr.active = 1", nativeQuery = true)
    List<User> findEncouragePushMsgTarget(Integer pushIdx, Integer readBook);

    static String readBookCondition(Integer readBook) {
        String readBookCondition = "AND NOT EXISTS ( SELECT 1 FROM t_user_study us WHERE us.user_idx = usr.id ) ";
        if ( readBook != null ) return "";
        if ( readBook != 0 ) readBookCondition.replace("NOT", "");
        return readBookCondition;
    }

【问题讨论】：

标签： spring-boot jpa dynamicquery nativequery

【解决方案1】：

您可以使用 JPA 规范编写动态查询。参考：Spring data JPA Specification

【讨论】：

我应该如何定义一个不会改变的查询？
您无法通过传递静态 JPA/SQL 查询来定义它相反，您应该调用相应的方法来构造 JPA 查询。 baeldung.com/hibernate-criteria-queries

【解决方案2】：

我假设你在if ( readBook != null ) return ""; 中犯了一个错误，它应该是if ( readBook == null ) return ""; 否则它永远不会进入下一个条件if ( readBook != 0 )...。

sql 中方法readBookCondition(readBook) 的等价物是：

AND NOT EXISTS ( SELECT 1 FROM t_user_study us WHERE us.user_idx = usr.id ) 
-- start of dynamic part
AND
    CASE
        WHEN :readBook IS NULL THEN 
            1 = 1
        ELSE 
            CASE 
                WHEN :readBook != 0 THEN 
                    EXISTS ( SELECT 1 FROM t_user_study us WHERE us.user_idx = usr.id )
                ELSE 
                    NOT EXISTS ( SELECT 1 FROM t_user_study us WHERE us.user_idx = usr.id )     
            END
    END
-- end of dynamic part
AND usr.active = 1;

根据您使用的数据库调整上述内容。

【讨论】：