**Note**: You must be specify `POSTGRESQL_HOST``POSTGRESQL_PORT``POSTGRESQL_DATABASE``POSTGRESQL_USERNAME``POSTGRESQL_PASSWORD``ZOOKEEPER_QUORUM` when start a standalone dolphinscheduler server.
**Note**: You must be specify `DATABASE_HOST``DATABASE_PORT``DATABASE_DATABASE``DATABASE_USERNAME``DATABASE_PASSWORD``ZOOKEEPER_QUORUM` when start a standalone dolphinscheduler server.
The Dolphin Scheduler image uses several environment variables which are easy to miss. While none of the variables are required, they may significantly aid you in using the image.
**`POSTGRESQL_HOST`**
**`DATABASE_TYPE`**
This environment variable sets the host for PostgreSQL. The default value is `127.0.0.1`.
This environment variable sets the type for database. The default value is `postgresql`.
**Note**: You must be specify it when start a standalone dolphinscheduler server. Like `master-server`, `worker-server`, `api-server`, `alert-server`.
**`POSTGRESQL_PORT`**
**`DATABASE_DRIVER`**
This environment variable sets the port for PostgreSQL. The default value is `5432`.
This environment variable sets the type for database. The default value is `org.postgresql.Driver`.
**Note**: You must be specify it when start a standalone dolphinscheduler server. Like `master-server`, `worker-server`, `api-server`, `alert-server`.
**Note**: You must be specify it when start a standalone dolphinscheduler server. Like `master-server`, `worker-server`, `api-server`, `alert-server`.
**`DATABASE_HOST`**
This environment variable sets the host for database. The default value is `127.0.0.1`.
**Note**: You must be specify it when start a standalone dolphinscheduler server. Like `master-server`, `worker-server`, `api-server`, `alert-server`.
**`DATABASE_PORT`**
This environment variable sets the port for database. The default value is `5432`.
**Note**: You must be specify it when start a standalone dolphinscheduler server. Like `master-server`, `worker-server`, `api-server`, `alert-server`.
**`DATABASE_USERNAME`**
This environment variable sets the username for database. The default value is `root`.
**Note**: You must be specify it when start a standalone dolphinscheduler server. Like `master-server`, `worker-server`, `api-server`, `alert-server`.
**`POSTGRESQL_USERNAME`**
**`DATABASE_PASSWORD`**
This environment variable sets the username for PostgreSQL. The default value is `root`.
This environment variable sets the password for database. The default value is `root`.
**Note**: You must be specify it when start a standalone dolphinscheduler server. Like `master-server`, `worker-server`, `api-server`, `alert-server`.
**`POSTGRESQL_PASSWORD`**
**`DATABASE_DATABASE`**
This environment variable sets the password for PostgreSQL. The default value is `root`.
This environment variable sets the database for database. The default value is `dolphinscheduler`.
**Note**: You must be specify it when start a standalone dolphinscheduler server. Like `master-server`, `worker-server`, `api-server`, `alert-server`.
**`POSTGRESQL_DATABASE`**
**`DATABASE_PARAMS`**
This environment variable sets the database for PostgreSQL. The default value is `dolphinscheduler`.
This environment variable sets the database for database. The default value is `characterEncoding=utf8`.
**Note**: You must be specify it when start a standalone dolphinscheduler server. Like `master-server`, `worker-server`, `api-server`, `alert-server`.