How To Generate Two Databases Via schema-*.sql And Match Entities To Them Via @Table In MySQL

Note: As a rule, in real applications avoid generating schema via hibernate.ddl-auto. Use schema-*.sql file or better Flyway or Liquibase.

Description: This application is an example of using schema-*.sql to generate two databases in MySQL. The databases are matched at entity mapping via @Table.

Key points:

• in application.properties, set the JDBC URL without the database, e.g., spring.datasource.url=jdbc:mysql://localhost:3306
• in application.properties, disable DDL auto (just don't specify hibernate.ddl-auto) or set it to validate
• in aaplication.properties, instruct Spring Boot to initialize the schema from schema-mysql.sql file
• in Author entity, specify that the corresponding table (author) is in the database authorsdb via @Table(schema="authorsdb")
• in Book entity, specify that the corresponding table (book) is in the database booksdb via @Table(schema="booksdb")

Output example:

• Persisting a Author results in the following SQL: insert into authorsdb.author (age, genre, name) values (?, ?, ?)
• Persisting a Book results the following SQL: insert into booksdb.book (isbn, title) values (?, ?)

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