Spring Data Rest：“日期为空”查询引发 postgres 异常

Question

我使用 Spring Boot 和 Data Rest 在 Java8 中创建了一个简单的微服务并获得了 postgres 异常。

我的实体：

@Entity
public class ArchivedInvoice implements Serializable {
    ...
    @Column
    private String invoiceNumber;
    @Column
    private java.sql.Date invoiceDate;
    ...
}

我的仓库界面：

@RepositoryRestResource(collectionResourceRel = "archivedinvoices", path = "archivedinvoices")
public interface ArchivedInvoiceRepository extends PagingAndSortingRepository < ArchivedInvoice, Long > {
    ...
@RestResource(rel = "findByXYZ", path = "findByXYZ")
@Query(value = "SELECT ai FROM #{#entityName} ai WHERE "
        + "(:invoiceNumber IS NULL OR ai.invoiceNumber LIKE :invoiceNumber) AND "
        + "(:invoiceDate IS NULL OR ai.invoiceDate = :invoiceDate)" 
        )
public Page < ArchivedInvoice > findByXYZ(
        @Param("invoiceNumber") @Nullable String invoiceNumber,
        @Param("invoiceDate") @Nullable Date invoiceDate,
        Pageable p);
    ...
}

如果我调用“.../findByXYZ?invoiceDate=2016-02-22”，我会收到以下错误消息：

org.springframework.dao.InvalidDataAccessResourceUsageException: could not extract ResultSet; SQL [n/a]; nested exception is org.hibernate.exception.SQLGrammarException: could not extract ResultSet
...
Caused by: org.hibernate.exception.SQLGrammarException: could not extract ResultSet
...
Caused by: org.postgresql.util.PSQLException: FEHLER: could not determine data type of parameter

但是，当我删除 ":invoiceDate IS NULL" 部分时，它可以工作。如果 invoiceDate 参数为空，如何检查？

Answer 1

我花了一些时间来研究这个，因为我真的想在查询中比较“日期为空”，这就是结果：

当您使用“cast(foo.date as date) is null”时，如果该字段不为空，则它可以正常工作。如果该字段为 null，则抛出此异常：

org.postgresql.util.PSQLException: ERROR: cannot cast type bytea to date

解决方案是使用合并：

coalesce(:date, null) is null

无论是否有现场测试的数据，它都可以正常工作。

我的查询示例：

@Query("SELECT c "
        + " FROM Entity c "
        + " WHERE "
        + "       and ( (coalesce(:dateFrom, null) is null and coalesce(:dateUntil, null) is null) "
        + "             or ((coalesce(c.date, null) is not null) "
        + "                 and ( "
        + "                        ((coalesce(:dateFrom, null) is null and coalesce(:dateUntil, null) is not null) and c.date <= :dateUntil) "
        + "                     or ((coalesce(:dateUntil, null) is null and coalesce(:dateFrom, null) is not null) and c.date >= :dateFrom)"
        + "                     or (c.date between :dateFrom and :dateUntil)"
        + "                 )"
        + "             )"
        + "       ) "

希望它对你有用！

Answer 2

我在 postgres 9.5 中对 LocalDateTime 类型的字段和 Timestamp 字段有类似的问题。 我解决了它，像这样转换它：

    @Query("SELECT c "
        + "FROM Contract c "
        + "WHERE "
        + "(:idContract IS NULL OR c.idContract = :idContract) AND "
        + "(CAST(:dtCancelInitial AS java.time.LocalDateTime) IS NULL OR (c.dtCancel >= :dtCancelInitial AND c.dtCancel < :dtCancelFinal)) "
        + "ORDER BY c.idContract")
List<Contract> findContratConsultaCancelamento(@Param("idContract") Long idContract, @Param("dtCancelInitial") LocalDateTime dtCancelInitial, @Param("dtCancelFinal") LocalDateTime dtCancelFinal);

Answer 3

我相信@Bonifacio 是正确的，因为在执行IS NULL 测试时，Postgres 无法确定您的@Param("invoiceDate") 参数的类型。我有与您的查询类似的查询，它们在内存 H2 数据库中的行为与预期一样，但在 Postgres 集成测试中失败。

我可以通过将参数转换为这样的日期来解决这个问题：

@Query(value = "SELECT ai FROM #{#entityName} ai WHERE "
    + "(:invoiceNumber IS NULL OR ai.invoiceNumber LIKE :invoiceNumber) AND "
    + "(cast(:invoiceDate as date) IS NULL OR ai.invoiceDate = :invoiceDate)" 
    )

Answer 4

当您将 JPA 与 Postgres 一起使用时，当您想在稍后检查所需条件之前检查参数是否为空时，会出现一种奇怪的行为，这将导致错误。

发生错误是因为在读取查询时，JPA 无法识别参数类型，然后在解释查询时引发错误。

解决方法是切换参数条件的位置，首先检查所需条件是否为真，然后检查参数是否为空。

这样，JPA 将能够识别正确的参数类型，并且不会再次引发错误。

尝试以下查询，看看它是否有效：

@Query(value = "SELECT ai FROM #{#entityName} ai WHERE "
    + "(:invoiceNumber IS NULL OR ai.invoiceNumber LIKE :invoiceNumber) AND "
    + "(ai.invoiceDate = :invoiceDate OR :invoiceDate IS NULL)" 
    )