JPA，SQlite没有这样的表格:SEQUENCE [英] JPA, SQlite no such table: SEQUENCE

问题描述

我在使用JPA和SQlite时遇到问题.

I have a problem with JPA and SQlite.

我已经从表创建了一个实体.我生成的实体看起来像:

I have created an Entity from Table. My generated Entity looks like:

    @Entity
    @Table(name="sqliteTestTable")
    public class Test implements Serializable {
        private static final long serialVersionUID = 1L;

        @Id  
        @GeneratedValue(strategy=GenerationType.IDENTITY)
        @Column(name="id")
        private int id;

        @Column(name="name")
        private String name;



        public Test() {
        }
        ------
    }

当我尝试保留一些测试对象时，出现以下错误: (我已经在mysql上执行了相同的代码而没有问题)

When i try to persist a few Test objects i get following error: (I have executed the same code on mysql without problems)

Exception in thread "main" Local Exception Stack: 
Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.4.1.v20121003-ad44345): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: no such table: SEQUENCE
Error Code: 0
Call: UPDATE SEQUENCE SET SEQ_COUNT = SEQ_COUNT + ? WHERE SEQ_NAME = ?
    bind => [50, SEQ_GEN_TABLE]
Query: DataModifyQuery(name="SEQ_GEN_TABLE" sql="UPDATE SEQUENCE SET SEQ_COUNT = SEQ_COUNT + ? WHERE SEQ_NAME = ?")
    at org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:333)

我该如何解决这个问题?

How can i solve this problem?

推荐答案

如果数据库平台不支持IDENTITY，则IDENTITY将默认为TABLE.

IDENTITY will default to TABLE if IDENTITY is not supported in the database platform.

对于TABLE，您需要创建一个序列表.如果您有ElipseLink创建表，它将自动为您创建表，否则，您需要自己创建它.

For TABLE you need to have a sequence table created. If you have ElipseLink create your tables it will automatically be created for you, otherwise you need to create it yourself.

如果SQlite具有IDENTITY支持，则可以创建自己的DatabasePlatform子类来添加身份支持.

If SQlite has IDENTITY support, then you can create your own DatabasePlatform subclass that adds the identity support.

通常，我永远不建议使用IDENTITY，它不支持预分配，并且会导致性能下降.

In general I would never recommend using IDENTITY, it does not support pre-allocation and will lead to poor performance.

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