exposed-migration

Exposed Migration

This sample project illustrates how to:

• generate a migration script using Exposed
• apply a migration using a third-party library like Flyway with a migration script generated by Exposed

Generating a migration script

To simulate applying a migration on an existing database, the database in this sample project is initially set up using raw SQL in the function simulateExistingDatabase. In Tables.kt, the table Users represents the modified version of the Users table, which was created in simulateExistingDatabase and does not have a primary key.

The function MigrationUtils.generateMigrationScript generates a SQL migration script in the specified directory. The exposed-migration dependency is needed for this. In this sample project, it will be generated inside a directory called migrations.

implementation("org.jetbrains.exposed:exposed-migration:$exposedVersion")

The generated migration script can also be edited manually before applying a migration. In this sample project, it will be generated inside a directory called migrations.

To generate the migration script for this project, execute the following command in the repository's root directory:

./gradlew generateMigrationScript

Applying a migration

In this sample project, Flyway is set up to apply migrations using migration scripts in the directory where Exposed generates them. It is recommended to apply the migration in a separate transaction.

Running

To apply the database migration for this project, execute the following command in the repository's root directory:

./gradlew run