use Hibernate automatic Dialect resolution

[xtyuns]

SpringBoot: 3.2.5
SpringFramework: v6.1.6
Hibernate: 6.4.4

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When I start the springboot application I see the warning message in the logs:

WARN --- [           main] org.hibernate.orm.deprecation            153 : HHH90000025: MySQLDialect does not need to be specified explicitly using 'hibernate.dialect' (remove the property setting and it will be selected by default)

So I tried to remove the configuration entry in applicaiton.properties: spring.jpa.properties.hibernate.dialect, but the warning message still appears after restarting the application.

Then I found the reason through the debugger, this warning message is from Hibernate:
https://github.com/hibernate/hibernate-orm/blob/6.4.4/hibernate-core/src/main/java/org/hibernate/engine/jdbc/dialect/internal/DialectFactoryImpl.java#L152-L154

Because there is a configuration content about hibernate.dialect here:
https://github.com/hibernate/hibernate-orm/blob/6.4.4/hibernate-core/src/main/java/org/hibernate/engine/jdbc/dialect/internal/DialectFactoryImpl.java#L85-L88

It is from:

spring-framework/spring-orm/src/main/java/org/springframework/orm/jpa/vendor/HibernateJpaVendorAdapter.java

Lines 150 to 155 in b932df6

	else {
	Class<?> databaseDialectClass = determineDatabaseDialectClass(getDatabase());
	if (databaseDialectClass != null) {
	jpaProperties.put(AvailableSettings.DIALECT, databaseDialectClass.getName());
	}
	}

It looks like I can't use Hibernate automatic Dialect resolution and it keeps warning me about removing the default configuration.

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I'm not sure if it's a good idea to remove this default detection of determineDatabaseDialectClass, and I found this: #22326

[snicoll]

Spring Framework does not use an automatic dialect resolution unless you create the EMF yourself or use a database vendor. We can't say for sure how you end up in this situation as you haven't shared what your application is doing.

Please review the recommendation in #31889 (comment). If that doesn't help, please share a small sample we can run ourselves and we can reopen this issue.