Often products are required to integrate with external resources such as databases, files, s3, etc. Sometimes we integrate with legacy systems with customers, which nothing supports, so a custom integration code is ok. If we have to integrate with many common external resources and even provide a join between them, we can use the TEIID open source project as an integration layer. TEIID delivers a virtual layer to join information such as LDAP, many databases, S3, CSV, Google Sheets, etc. From the client’s perspective, it behaves like a standard JDBC driver (very similar to a PostgreSQL syntax).