destructive
Performs a destructive migration on the provided SQL driver.
This method drops all tables from the database, excluding system tables like sqlite_sequence and android_metadata. After all tables are dropped, the schema is recreated using the create method.
Receiver
The SqlSchema that defines the structure of the database.
Return
A QueryResult.AsyncValue<Unit> representing the result of the migration process. The schema is recreated after all tables are dropped.
Example:
object DestructiveMigrationSchema :
SqlSchema<QueryResult.AsyncValue<Unit>> by MyClientDatabase.Schema {
override fun migrate(
driver: SqlDriver, oldVersion: Long, newVersion: Long, vararg callbacks: AfterVersion
): QueryResult.AsyncValue<Unit> {
Log.d(
MyClientManager.TAG,
"Database version changed ($oldVersion -> $newVersion), performing destructive migration"
)
return destructiveMigration(driver)
}
}
fun MynClientDatabase.Companion.DestructiveMigrationSchema():
SqlSchema<QueryResult.AsyncValue<Unit>> = DestructiveMigrationSchemaIn this example, the DestructiveMigrationSchema object implements the SqlSchema interface. When the migrate method detects a version change, it logs the change and invokes destructiveMigration(driver) to drop and recreate all tables.
Parameters
The SqlDriver instance that will be used to execute the SQL commands.