我正在构建一个 Spring MVC 应用程序，有人可以在其中填写表单，如果单击发送，则表单数据将保存在数据库中。我正在使用 spring-data-jpa。但是当我填写表格并单击发送时，它显示 HTTP 状态 500 错误。我遵循了每个步骤，但它不起作用。这是我的联系人模型、联系人服务和联系人存储库以及错误 ---> Error::::
HTTP Status 500 - Request processing failed; nested exception is org.springframework.dao.InvalidDataAccessResourceUsageException: error performing isolated work; SQL [n/a]; nested exception is org.hibernate.exception.SQLGrammarException: error performing isolated work
type Exception report
message Request processing failed; nested exception is org.springframework.dao.InvalidDataAccessResourceUsageException: error performing isolated work; SQL [n/a]; nested exception is org.hibernate.exception.SQLGrammarException: error performing isolated work
description The server encountered an internal error that prevented it from fulfilling this request.
exception
org.springframework.web.util.NestedServletException: Request processing failed; …