Since I bumped to spring-boot 2.3.0 (which comes with hibernate-orm 5.4.15.Final) I got a severe issue at startup (app doesn't even start).
Oracle 11g / Oracle10gDialect
spring.jpa.hibernate.ddl-auto: validate (because of legacy context, deactivate ddl validation is not an option)
It fails with this message on one of my entity (the sequence is of course existing):
[PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is org.hibernate.tool.schema.spi.SchemaManagementException: Schema-validation: missing sequence [seq_canal]
Same code was working with spring boot 2.2.6 (hibernate 5.4.12.Final)
Oracle 11G, Oracle10gDialect