Hibernate + Derby：不支持'BOOLEAN'和'INTEGER'之间的比较 [英] Hibernate + Derby: Comparisons between 'BOOLEAN' and 'INTEGER' are not supported

问题描述

我在查询Derby数据库时遇到问题。我正在使用Hibernate和JPA。问题与布尔列相关（可能）。每个查询以错误结束：

org.hibernate.exception.SQLGrammarException：不支持'BOOLEAN'和'INTEGER'之间的比较。类型必须具有可比性。字符串类型也必须具有匹配的排序规则。如果排序规则不匹配，则可能的解决方案是将操作数强制转换为默认排序规则（例如，SELECT tablename FROM sys.systables WHERE CAST（tablename AS VARCHAR（128））='T1'）

您可以在下面找到示例代码和配置。样本被简化以便于阅读。这是我的JPA实体：

  @Entity 
公共抽象类任务实现Serializable {
 
 @Id 
 @GeneratedValue（strategy = GenerationType.TABLE）
保护长ID; 
 
 @Column 
保护布尔值已删除; 
 
 public long getId（）{
 return id; 
} 
 
 public boolean isDeleted（）{
 return deleted; 
} 
 
 public void setId（long id）{
 this.id = id; 
} 
 
 public void setDeleted（boolean deleted）{
 this.deleted = deleted; 
} 
 
 @Override 
 public int hashCode（）{
 return id; 
} 
 
 @Override 
 public boolean equals（Object object）{
 if（object == null）{
 return false; $！
 
 
 if（！this.getClass（）。equals（object.getClass（）））{
 return false; 
} 
 
 EntityObject other =（EntityObject）对象; 
 
 if（this.id！= other.id）{
 return false; 
} 
 
返回true; 
} 
 
 @Override 
 public String toString（）{
 returnEntityObject [id =+ id +]; 
} 
} 
  

我的JPA查询：

  SELECT t FROM任务t WHERE删除= false 
  

我的JPA配置：

 < persistence-unit name =PU1transaction-type =JTA > 
< provider> org.hibernate.ejb.HibernatePersistence< / provider> 
< jta-data-source> jdbc / myapp< / jta-data-source> 
< exclude-unlisted-classes> false< / exclude-unlisted-classes> 
<属性> 
< property name =hibernate.hbm2ddl.autovalue =update/> 
< property name =hibernate.dialectvalue =org.hibernate.dialect.DerbyDialect/> 
< / properties> 
< / persistence-unit> 
  

有什么不对？如何解决这个问题？感谢您的任何建议。

解决方案

降级没有帮助。这是适用于我的有效解决方案：

  import java.sql.Types; 
 import org.hibernate.dialect.DerbyTenSevenDialect; 
 
 public class DerbyDialect extends DerbyTenSevenDialect {
 
 public DerbyDialect（）{
 //修复Derby方言布尔数据类型映射错误
 registerColumnType（Types.BOOLEAN ， 整数）; 
} 
} 
  

我想最好配置'true'和'false'常量在方言中映射到Derby数据类型，但上面已经足够了。

I have a problem with querying Derby database. I am using Hibernate with JPA. Problem is related (probably) to boolean columns. Each query ends with error:

org.hibernate.exception.SQLGrammarException: Comparisons between 'BOOLEAN' and 'INTEGER' are not supported. Types must be comparable. String types must also have matching collation. If collation does not match, a possible solution is to cast operands to force them to the default collation (e.g. SELECT tablename FROM sys.systables WHERE CAST(tablename AS VARCHAR(128)) = 'T1')

Below you may find sample code and configuration. Samples are simplified for easier reading. Here is my JPA entity:

@Entity
public abstract class Task implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.TABLE)
    protected long id;

    @Column
    protected boolean deleted;

    public long getId() {
        return id;
    }

    public boolean isDeleted() {
        return deleted;
    }

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

    public void setDeleted(boolean deleted) {
        this.deleted = deleted;
    }

    @Override
    public int hashCode() {
        return id;
    }

    @Override
    public boolean equals(Object object) {
        if (object == null) {
            return false;
        }

        if (!this.getClass().equals(object.getClass())) {
            return false;
        }

        EntityObject other = (EntityObject) object;

        if (this.id != other.id) {
            return false;
        }

        return true;
    }

    @Override
    public String toString() {
        return "EntityObject[ id=" + id + " ]";
    }
}

My JPA query:

SELECT t FROM Task t WHERE deleted = false

My JPA configuration:

<persistence-unit name="PU1" transaction-type="JTA">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<jta-data-source>jdbc/myapp</jta-data-source>
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<properties>
  <property name="hibernate.hbm2ddl.auto" value="update"/>
  <property name="hibernate.dialect" value="org.hibernate.dialect.DerbyDialect"/>
</properties>
</persistence-unit>

What is wrong? How to fix that? Thanks for any suggestions.

解决方案

Downgrade didn't helped. Here is valid solution which works for me:

import java.sql.Types;
import org.hibernate.dialect.DerbyTenSevenDialect;

public class DerbyDialect extends DerbyTenSevenDialect {

    public DerbyDialect() {
        // fix Derby dialect boolean data type mapping error
        registerColumnType(Types.BOOLEAN, "INTEGER");
    }
}

I guess it is better to configure 'true' and 'false' constants mapping in dialect to Derby data type, but above is good enough for now.

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