小编Emm*_*eng的帖子

伙计们。我在 Spring boot 2.3.0 和 PostgreSQL 12 项目中遇到问题。我有一个名为User的实体类，其代码如下：

@Entity\n@NoArgsConstructor\n@Data\n@AllArgsConstructor\n@Builder\npublic class User {\n    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)\n    private Long id;\n    private String username;\n    private String email;\n    private String firstName;\n    private String lastName;\n    private int age;\n}\n

我的 application.properties 文件如下所示：

spring.jpa.hibernate.ddl-auto=create-drop\nspring.jpa.hibernate.show-sql=true\nspring.datasource.url=jdbc:postgresql://localhost:5432/dbname\nspring.datasource.username=postgres\nspring.datasource.password=*********\n

担心的是，当我执行我的项目时，我会遇到这样的错误：

org.hibernate.tool.schema.spi.CommandAcceptanceException: Error executing DDL "drop table if exists user cascade" via JDBC Statement\n    at org.hibernate.tool.schema.internal.exec.GenerationTargetToDatabase.accept(GenerationTargetToDatabase.java:67) ~[hibernate-core-5.4.15.Final.jar:5.4.15.Final]\n    at org.hibernate.tool.schema.internal.SchemaDropperImpl.applySqlString(SchemaDropperImpl.java:375) [hibernate-core-5.4.15.Final.jar:5.4.15.Final]\n    at org.hibernate.tool.schema.internal.SchemaDropperImpl.applySqlStrings(SchemaDropperImpl.java:359) [hibernate-core-5.4.15.Final.jar:5.4.15.Final]\n    at org.hibernate.tool.schema.internal.SchemaDropperImpl.dropFromMetadata(SchemaDropperImpl.java:241) [hibernate-core-5.4.15.Final.jar:5.4.15.Final]\n    at org.hibernate.tool.schema.internal.SchemaDropperImpl.performDrop(SchemaDropperImpl.java:154) [hibernate-core-5.4.15.Final.jar:5.4.15.Final]\n    at org.hibernate.tool.schema.internal.SchemaDropperImpl.doDrop(SchemaDropperImpl.java:126) [hibernate-core-5.4.15.Final.jar:5.4.15.Final]\n    at org.hibernate.tool.schema.internal.SchemaDropperImpl.doDrop(SchemaDropperImpl.java:112) [hibernate-core-5.4.15.Final.jar:5.4.15.Final]\n    at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.performDatabaseAction(SchemaManagementToolCoordinator.java:145) …