I am integrating spring boot + jpa + oracle. I was successful in creating and drop the database with spring.jpa.hibernate.ddl-auto=create-drop, but when I change the property to spring.jpa.hibernate.ddl-auto=update, spring boot hangs up and the application is not starting up.
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 :: Spring Boot ::        (v2.3.1.RELEASE)
2021-01-03 00:54:49.024  INFO 40612 --- [           main] com.walmart.DemoApplication     : Starting DemoApplication on m-c02dj138ml85 with PID 40612 (/Users/b0j02tw/Documents/demo/target/classes started by b0j02tw in /Users/b0j02tw/Documents/demo)
2021-01-03 00:54:49.026  INFO 40612 --- [           main] com.walmart.DemoApplication     : No active profile set, falling back to default profiles: default
2021-01-03 00:54:49.325  INFO 40612 --- [           main] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data JPA repositories in DEFERRED mode.
2021-01-03 00:54:49.367  INFO 40612 --- [           main] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 35ms. Found 1 JPA repository interfaces.
2021-01-03 00:54:49.656  INFO 40612 --- [           main] o.s.s.concurrent.ThreadPoolTaskExecutor  : Initializing ExecutorService 'applicationTaskExecutor'
2021-01-03 00:54:49.684  INFO 40612 --- [         task-1] o.hibernate.jpa.internal.util.LogHelper  : HHH000204: Processing PersistenceUnitInfo [name: default]
2021-01-03 00:54:49.719  INFO 40612 --- [         task-1] org.hibernate.Version                    : HHH000412: Hibernate ORM core version 5.4.17.Final
2021-01-03 00:54:49.733  INFO 40612 --- [           main] DeferredRepositoryInitializationListener : Triggering deferred initialization of Spring Data repositories…
2021-01-03 00:54:49.823  INFO 40612 --- [         task-1] o.hibernate.annotations.common.Version   : HCANN000001: Hibernate Commons Annotations {5.1.0.Final}
2021-01-03 00:54:49.891  INFO 40612 --- [         task-1] com.zaxxer.hikari.HikariDataSource       : HikariPool-1 - Starting...
2021-01-03 00:54:53.118  INFO 40612 --- [         task-1] com.zaxxer.hikari.HikariDataSource       : HikariPool-1 - Start completed.
2021-01-03 00:54:53.148  INFO 40612 --- [         task-1] org.hibernate.dialect.Dialect            : HHH000400: Using dialect: org.hibernate.dialect.Oracle10gDialect
application.properties:
#==== Looging properties ======#
#debug=true
#==== Looging root levels - TRACE, DEBUG, INFO, WARN, ERROR, OFF ======#
logging.level.root=INFO
spring.datasource.driver-class-name=oracle.jdbc.OracleDriver
##===== START - OracleDB connection settings ======#
spring.datasource.url=jdbc:oracle:thin:@//****
spring.datasource.username=***
spring.datasource.password=******
spring.jpa.hibernate.ddl-auto=update
##===== END - OracleDB connection settings ======#
#
##====== START - JPA settings ======
##===== END - OracleDB connection settins ======#
#
#SQL FOR DEBUGGING
spring.jpa.show-sql=true
 
     
    