How to auto-create a database on connection?

Question

MySQL

Hello, I'm new to Java Spring, For starters, it's worth showing the code and not asking the application.properties question :

server.port = 8080

spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/
spring.datasource.username=root

so everything works fine, but I need to create a database when connecting to the mysql server, I write the code so that when I connect, the necessary database is created

server.port = 8080

spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/mydb
spring.datasource.username=root

And there is a huge error in the output:

java.sql.SQLSyntaxErrorException: Unknown database 'mydb'
  at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:120) ~[mysql-connector-java-8.0.22.jar:8.0.22]
  at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) ~[mysql-connector-java-8.0.22.jar:8.0.22]
  at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122) ~[mysql-connector-java-8.0.22.jar:8.0.22]
  at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:836) ~[mysql-connector-java-8.0.22.jar:8.0.22]
  at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:456) ~[mysql-connector-java-8.0.22.jar:8.0.22]
  at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:246) ~[mysql-connector-java-8.0.22.jar:8.0.22]
  at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:198) ~[mysql-connector-java-8.0.22.jar:8.0.22]
  at com.zaxxer.hikari.util.DriverDataSource.getConnection(DriverDataSource.java:138) ~[HikariCP-3.4.5.jar:na]
  at com.zaxxer.hikari.pool.PoolBase.newConnection(PoolBase.java:358) ~[HikariCP-3.4.5.jar:na]
  at com.zaxxer.hikari.pool.PoolBase.newPoolEntry(PoolBase.java:206) ~[HikariCP-3.4.5.jar:na]
  at com.zaxxer.hikari.pool.HikariPool.createPoolEntry(HikariPool.java:477) ~[HikariCP-3.4.5.jar:na]
  at com.zaxxer.hikari.pool.HikariPool.checkFailFast(HikariPool.java:560) ~[HikariCP-3.4.5.jar:na]
  at com.zaxxer.hikari.pool.HikariPool.<init>(HikariPool.java:115) ~[HikariCP-3.4.5.jar:na]
  at com.zaxxer.hikari.HikariDataSource.getConnection(HikariDataSource.java:112) ~[HikariCP-3.4.5.jar:na]
  at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:122) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator$ConnectionProviderJdbcConnectionAccess.obtainConnection(JdbcEnvironmentInitiator.java:180) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:68) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:35) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:101) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:263) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:237) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:214) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.id.factory.internal.DefaultIdentifierGeneratorFactory.injectServices(DefaultIdentifierGeneratorFactory.java:152) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.service.internal.AbstractServiceRegistryImpl.injectDependencies(AbstractServiceRegistryImpl.java:286) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:243) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:214) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.<init>(InFlightMetadataCollectorImpl.java:176) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:127) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:1224) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:1255) ~[hibernate-core-5.4.27.Final.jar:5.4.27.Final]
  at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:58) ~[spring-orm-5.3.3.jar:5.3.3]
  at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365) ~[spring-orm-5.3.3.jar:5.3.3]
  at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:409) ~[spring-orm-5.3.3.jar:5.3.3]
  at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:396) ~[spring-orm-5.3.3.jar:5.3.3]
  at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.afterPropertiesSet(LocalContainerEntityManagerFactoryBean.java:341) ~[spring-orm-5.3.3.jar:5.3.3]
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1847) ~[spring-beans-5.3.3.jar:5.3.3]
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1784) ~[spring-beans-5.3.3.jar:5.3.3]
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:609) ~[spring-beans-5.3.3.jar:5.3.3]
  at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:531) ~[spring-beans-5.3.3.jar:5.3.3]
  at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.3.jar:5.3.3]
  at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.3.jar:5.3.3]
  at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.3.jar:5.3.3]
  at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.3.jar:5.3.3]
  at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1159) ~[spring-context-5.3.3.jar:5.3.3]
  at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:913) ~[spring-context-5.3.3.jar:5.3.3]
  at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:588) ~[spring-context-5.3.3.jar:5.3.3]
  at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:144) ~[spring-boot-2.4.2.jar:2.4.2]
  at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:767) ~[spring-boot-2.4.2.jar:2.4.2]
  at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) ~[spring-boot-2.4.2.jar:2.4.2]
  at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:426) ~[spring-boot-2.4.2.jar:2.4.2]
  at org.springframework.boot.SpringApplication.run(SpringApplication.java:326) ~[spring-boot-2.4.2.jar:2.4.2]
  at org.springframework.boot.SpringApplication.run(SpringApplication.java:1311) ~[spring-boot-2.4.2.jar:2.4.2]
  at org.springframework.boot.SpringApplication.run(SpringApplication.java:1300) ~[spring-boot-2.4.2.jar:2.4.2]
  at com.nzcoder.demo.NZcoderApplication.main(NZcoderApplication.java:10) ~[classes/:na]
  at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
  at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64) ~[na:na]
  at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
  at java.base/java.lang.reflect.Method.invoke(Method.java:564) ~[na:na]
  at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.4.2.jar:2.4.2]

This is not the whole mistake, but I think it is clear that the application does not find the required database, instead of creating a database and then connecting to it.

Question: how to create a database when connecting?

Answer 1

This is of course not an answer to the question itself, but are you sure that

I need to create a database when connecting to mysql server

?
Think again about this, most likely you are mistaken.
I am almost 100% sure that what you want to do is not the right approach in principle.
By and large, the base and its structure should be created and (if necessary) filled with something at the deployment stage (or installation, whatever you want to call it). Those. the application should not create and change the structure of the database (an exception is an application for which this is their direct function, such as any clients for working with databases).
I note that creating a table (in its absence) and creating a database are, to put it mildly, not the same thing, but if possible, your application should not even create / change tables (I repeat - all work on creating a database and / or creating / changing its structure this is only at the deployment stage, but not when the application is running)
ps

I write the code so that when I connect, the necessary database is created for me

server.port = 8080

spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/mydb
spring.datasource.username=root

And why did you decide that with such a config, when connecting, the database you need will be created?

Answer 2

Try adding
hibernate.hbm2ddl.auto=create
Here a list of all possible options:
https://docs.jboss.org/hibernate/orm/5.2/userguide...