Starting an OLAP Database

The Doradus server is configured as an OLAP database when the following option is used in the doradus.yaml file:

storage_services:

- com.dell.doradus.service.olap.OLAPService

When the Doradus server starts, this option initializes the OLAPService and places new applications under the control of OLAP storage by default. Details of installing and configuring the Doradus server are covered in the Doradus Administration document, but here’s a review of three ways to start Doradus:

•	Standalone: The Doradus server can be started as a standalone application using the provided Jetty web server to serve the REST API. When Doradus is built using Maven, an example command line from the directory {doradus_home}/doradus-jetty is:

java -cp ./target/classes:./target/dependency/* com.dell.doradus.core.DoradusServer

Command line arguments can be added to such as “-restport 5711” to change the REST API port to 5711.

•	Tomcat: Doradus can use Apache Tomcat to host its REST API. The doradus-tomcat folder provides a README file with instructions.

•	Windows service: Doradus can be started as a Windows service by using the procrun package from Apache Commons. See the Doradus Administration document for details.

•	Embedded app: Doradus can be embedded in another JVM process. It is started by calling the following method:

com.dell.doradus.core.DoradusServer.startEmbedded(String[] args, String[] services)

where:

•	args is the same arguments parameter passed to main() when started as a console application. For example {"-restport", "5711"} sets the REST port to 5711.

•

services is the list of Doradus services to initialize. Each string must be the full package name of a service. Required services are automatically included. An embedded application must include at least one storage service. Other services should be included when the corresponding functionality is needed. See the comments in doradus.yaml for a list of the current services.

If the Doradus server is configured to use multiple storage services, or if OLAP is not the default storage service (the first one listed in doradus.yaml), an application can explicitly choose OLAP in its schema by setting the application-level StorageService option to OLAPService. For example, in JSON:

{"Email": {

"options": {"StorageService": "OLAPService"},

...

}