What is a schema manager in Spring's Hibernate and how I set it? - postgresql

Question

Some tables were dropped at development environment during a spring-data-jpa project test and the developer responsible for it said it only used spring.jpa.hibernate.ddl-auto=update. Checking here, I suspected he had it set as create-drop, but since he said he didn't use, I went for this piece of information:
Spring Boot chooses a default value for you based on whether it thinks your database is embedded.
It defaults to create-drop if no schema manager has been detected
Since his application actually managed to connect to our development environment PostgreSQL database (since it dropped some tables), I start to think he maybe could have forgotten to set hbm2ddl.auto and automatically it went as create-drop.
Is it possible to connect to PostgreSQL and don't have a valid schema manager defined? Which are the most common schema managers?
PS: at this application #DataSource is set this way:
#Bean
public DataSource dataSource() {
Class.forName("org.postgresql.Driver");
DriverManagerDataSource dataSource = new DriverManagerDataSource();
dataSource.setUrl(someUrlConnectionStringFromApplicationDotPropertiesFile);
return dataSource;
}
like String someUrlConnectionStringFromApplicationDotPropertiesFile = "jdbc:postgresql://ipAddress:port/dbName?user=user&password=pass". I know spring-data-jpa sets everything with spring jpa properties automatically without this method, this is currently an unchangeable legacy code :(

Answer 1

Spring Boot said they are Higher-level Database Migration Tool (Flyway or Liquibase).
ref: https://docs.spring.io/spring-boot/docs/2.7.x/reference/html/howto.html#howto.data-access.jpa-properties, https://docs.spring.io/spring-boot/docs/2.7.x/reference/html/howto.html#howto.data-access.jpa-properties
You can also configure them through Spring Boot documentation or their own docs. ref: https://docs.spring.io/spring-boot/docs/2.7.x/reference/html/howto.html#howto.data-initialization.migration-tool
For example, configure Flyway community version through maven (https://flywaydb.org/download/community):
<build>
...
<plugin>
<groupId>org.flywaydb</groupId>
<artifactId>flyway-maven-plugin</artifactId>
<version>9.12.0</version>
</plugin>
...
</build>