Datasources are automatically created based on the value of some environment variables. The most important is the `*DB_SERVICE_PREFIX_MAPPING*` environment variable that defines JNDI mappings for data sources. This variable must be set to a comma-separated list of `*_=*` triplets, where `name` is used as the pool-name in the data source, `database_type` determines what database driver to use, and `PREFIX` is the prefix used in the names of environment variables, which are used to configure the data source. include::jndi_mappings.adoc[]