[Error] JPA H2 사용시 MySQL 설정할 때 에러 발생

H2로 만든 DB를 MySQL로 설정해서 MySQL의 방언으로 나가는 쿼리를 확인해 보고싶었는데..

에러가 무수히 많이 발생!!

9월 05, 2024 10:35:56 오후 org.hibernate.tool.schema.internal.ExceptionHandlerLoggedImpl handleException
WARN: GenerationTarget encountered exception accepting command : Error executing DDL "
    alter table MEMBERS 
       drop 
       foreign key FKg1rcvci69xqokrwi7895n05wj" via JDBC [Table "MEMBERS" not found (this database is empty);]
org.hibernate.tool.schema.spi.CommandAcceptanceException: Error executing DDL "
    alter table MEMBERS 
       drop 
       foreign key FKg1rcvci69xqokrwi7895n05wj" via JDBC [Table "MEMBERS" not found (this database is empty);]
	at org.hibernate.tool.schema.internal.exec.GenerationTargetToDatabase.accept(GenerationTargetToDatabase.java:94)
	at org.hibernate.tool.schema.internal.Helper.applySqlString(Helper.java:233)
	at org.hibernate.tool.schema.internal.Helper.applySqlStrings(Helper.java:217)
	at org.hibernate.tool.schema.internal.SchemaDropperImpl.applyConstraintDropping(SchemaDropperImpl.java:470)
	at org.hibernate.tool.schema.internal.SchemaDropperImpl.dropConstraintsTablesSequences(SchemaDropperImpl.java:242)
	at org.hibernate.tool.schema.internal.SchemaDropperImpl.dropFromMetadata(SchemaDropperImpl.java:215)
	at org.hibernate.tool.schema.internal.SchemaDropperImpl.performDrop(SchemaDropperImpl.java:185)
	at org.hibernate.tool.schema.internal.SchemaDropperImpl.doDrop(SchemaDropperImpl.java:155)
	at org.hibernate.tool.schema.internal.SchemaDropperImpl.doDrop(SchemaDropperImpl.java:115)
	at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.performDatabaseAction(SchemaManagementToolCoordinator.java:244)
	at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.lambda$process$5(SchemaManagementToolCoordinator.java:145)
	at java.base/java.util.HashMap.forEach(HashMap.java:1421)
	at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.process(SchemaManagementToolCoordinator.java:142)
	at org.hibernate.boot.internal.SessionFactoryObserverForSchemaExport.sessionFactoryCreated(SessionFactoryObserverForSchemaExport.java:37)
	at org.hibernate.internal.SessionFactoryObserverChain.sessionFactoryCreated(SessionFactoryObserverChain.java:35)
	at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:315)
	at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:450)
	at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:1507)
	at org.hibernate.jpa.HibernatePersistenceProvider.createEntityManagerFactory(HibernatePersistenceProvider.java:55)
	at jakarta.persistence.Persistence.createEntityManagerFactory(Persistence.java:80)
	at jakarta.persistence.Persistence.createEntityManagerFactory(Persistence.java:55)
	at hellojpa.Main.main(Main.java:10)
Caused by: org.h2.jdbc.JdbcSQLSyntaxErrorException: Table "MEMBERS" not found (this database is empty); SQL statement:

 

위의 에러도 있고 SEQ 관련된 테이블을 찾을 수 없다는 에러도 나왔음.

에러 자체가 너무 길어서 다 가져오기는 어려웠다.

 

나는 일단 persistence.xml에는 MySQLDialect로 잘 설정을 했고, H2 접속도 잘됐다.

 

알고보니 각 엔티티에 @GeneratedValue 어노테이션을 붙이고 strategy 속성을 안붙여주어 에러가 발생!

MySQL의 AutoIncrement를 사용하기 위해서 기본키 생성 전략을 IDENTITY로 변경했고 정상 동작!!

(PK 생성을 하이버네이트가 아닌 DB에 위임하기 위해서 GenerationType.IDENTITY를 설정해주어야 한다)