When performing data migration, it often involves a workflow where data needs to be extracted from multiple repositories, transformed, and then saved to new repositories. One approach to tackle this task is by utilizing Spring Batch processing. However, there is a limitation with the JpaRepositoryItemReader in Spring Batch, as it can only read from a single repository. How can I overcome this
A chunk-oriented step in Spring Batch can have only one reader. If you need to read from multiple sources, you can use the MultiResourceItemReader or the CompositeItemReader, otherwise implement a custom reader according to your needs.
Another option is to use multiple steps that aggregate data from different sources in the same staging area (which could be a database table or collection).