In 2.31 we are introducing Flyway as a new system for database migrations. In the process we have removed most of the legacy database migration statements/scripts in order to have a fresh start and to reduce startup time of the application. As a result, when migrating from older DHIS 2 versions it is required to install DHIS 2.30 before installing DHIS 2.31. This will ensure that older migration scripts are being executed.
PostgreSQL version 9.6 or higher is required. The minimum required version was previously 9.4. We recommend migrating straight to version 10 as it is well tested with DHIS 2 and contains several performance improvements over 9.x.
Support for memcached as application cache provider is removed. Please use Redis instead.
The system settings Enable email notifications and Enable SMS notifications have been removed. The corresponding user settings now default to true.
The Mapzen API is discontinued and removed from Maps app and Settings app.