Overview of Liquid Data Administration

This section provides an overview of administrative tasks for BEA Liquid Data for WebLogic^TM. It includes the following sections:

This document focuses on the use of the administrative tasks that you perform using the WebLogic Server Administration Console, a Web-based tool that has been extended in Liquid Data to include tabs for configuring and managing Liquid Data, accessed via a Liquid Data node in the left pane. For instructions on how to start and navigate the Administration Console, see Using the WLS Administration Console.

Note: This document assumes that you have already installed the BEA WebLogic Platform^TM (according to the instructions in Installing WebLogic Platform in the WebLogic Platform documentation) and the Liquid Data software (according to the instructions in Installing Liquid Data).

Liquid Data comes with a preconfigured Samples domain (ld_samples) from which you can run the startWebLogic command or associated Windows Start menu command to start the Liquid Data server. The Samples domain can serve as your starting point for working with the Liquid Data samples, or for developing and testing your own data access and aggregation solutions.

To use Liquid Data beyond the Samples server, you need to either create a new Liquid Data domain or add Liquid Data to an existing WebLogic domain. Thereafter, you start WebLogic Server and Liquid Data in the domain. For instructions on how to create WebLogic domains or add Liquid Data to an existing WebLogic domain, see Creating Liquid Data Domains. In addition, for detailed instructions on deploying Liquid Data in various domain configurations, see Deployment Tasks in Deploying Liquid Data.

To configure and manage Liquid Data, you need to start a Liquid Data server in the WebLogic domain in which you want to work and access the WLS Administration Console for that server.

Before Liquid Data can retrieve information from a data source, access to the data source must be configured in the Administration Console. For each data source accessed in a Liquid Data query, you need to configure a data source description using the Data Sources tab on the Liquid Data node in the Administration Console. Additional configuration tasks are required for certain data source types. For detailed instructions, see Viewing and Accessing All Configured Data Sources.

A data source description is a group of configuration settings that Liquid Data uses to access a particular data source. Liquid Data requires a configured data source description before it can retrieve information from the data source. You use the Data Sources tab on the Liquid Data node in the Administration Console to create, edit, and remove data source descriptions and assign ACLs. The information stored in a data source description varies by data source type, as described in Supported Data Source Types.

After you have created a Liquid Data data source description for a data source in the WebLogic Server Administration Console, the data source you configured will show up as a data source on the Builder Toolbar in the Data View Builder. You can then use the Data View Builder to create data views and queries of the information in the data source, often in combination with information from other configured data sources. Alternatively, you can submit hand-coded, ad hoc queries to the Liquid Data server without using the Data View Builder. You can also invoke Liquid Data stored queries as EJB clients, JSP clients, or Web services clients. In all cases, the data sources must be configured first.

The Liquid Data Server supports the use of the following data sources in queries:

Table 1-1 Supported Data Source Types

Type	Where to Find Configuration Instructions
Relational databases	Configuring Access to Relational Databases
XML files	Configuring Access to XML Files
Web services	Configuring Access to Web Services
Application views	Configuring Access to Application Views
Data views	Configuring Access to Data Views

The steps required to make a data source available to Liquid Data server (and thereby to the Data View Builder) depend on the type of data source that you want to work with. For example, to make a relational database available to the Liquid Data Server, you first need to configure a JDBC connection pool and a JDBC data source that uses the connection pool, and then create the Liquid Data data source description for the relational database. Similarly, configuring access to an XML file or data view involves storing the XML file or data view file in the Liquid Data Server repository, then creating a data source description to find the appropriate file.

The server repository is the central location for storing and sharing stored queries, data views, XML data, source and target schemas, Web service WSDL files, generated Web services, and custom function libraries.

You need to configure the location of the server repository on the General tab on the Liquid Data node in the Administration Console, as described in Configuring Liquid Data Server Settings. You also need to populate and configure the repository on the Repository tab on the Liquid Data node in the Administration Console. For instructions, see Managing the Liquid Data Server Repository.

WebLogic Server provides the foundation for Liquid Data security. Liquid Data deployments can use the full range of security features that WebLogic Server provides, including security realms, users and groups, Access Control Lists (ACLs) and permissions, and so on. Liquid Data uses ACLs to control how users access and execute a query, and how users access specific data source elements (such as particular tables in a database, service calls in an application view, or a web service) for ad hoc queries or custom functions.

At a minimum, you must set up basic security according to the instructions in Initial Security Setup. If you want to use Liquid Data security in this deployment, you must enable secure mode on the General tab on the Liquid Data node in the Administration Console, as described in Configuring Liquid Data Server Settings. In addition, you need to explicitly configure secure access to data source descriptions, the server repository, stored queries, and custom function descriptions, as described in Implementing Security.

Liquid Data can cache query results for stored queries (but not ad hoc queries) to enhance overall Liquid Data performance. If you want to cache results for stored queries in this deployment, you must explicitly enable results caching on the General tab on the Liquid Data node in the Administration Console, as described in Configuring Liquid Data Server Settings. In addition, for each stored query that you want cached, you need to explicitly configure its caching policy in the Repository, as described in Configuring the Query Results Cache.

Liquid Data provides a set of standard functions for use in creating queries and data views. Users can extend Liquid Data by creating custom functions to perform specialized tasks. If custom functions are used in this deployment, you need to configure access to them, as described in Configuring Access to Custom Functions.

If you need to copy your Liquid Data server configuration to another server (such as from a development environment to a production environment), you can use the Administration Console to export the Liquid Data server configuration from the source server and import it on a target server. For more information, see Importing and Exporting Liquid Data Configurations, and also "Copying a Server Configuration to Another Server" in Deployment Tasks in Deploying Liquid Data.

Liquid Data is deployed as an enterprise archive file (LDS.ear) on a WebLogic domain. For instructions on how to deploy the LDS.ear file, see Deploying Liquid Data Components. For detailed information about deploying Liquid Data in various types of WebLogic domains, see Deployment Tasks in Deploying Liquid Data.

Using the Administration Console, you can publish Liquid Data stored queries as Web services. Web-based applications can then invoke Liquid Data queries as Web service clients. For more information, see Generating and Publishing Web Services.

Ongoing managing and monitoring tasks include starting and stopping the server; updating data source configurations; and setting up and monitoring logs and reports on Liquid Data Server performance and lifecycle.

It is a good practice to frequently export you Liquid Data configuration and to store the resulting file in a secure environment. This is especially the case whenever you change your Liquid Data configuration since a recently exported configuration will allow you to "roll back" in case of problems with your new configuration or its interaction with the Platform server. For more information, see Importing and Exporting Liquid Data Configurations, and also "Copying a Server Configuration to Another Server" in Deployment Tasks in Deploying Liquid Data.

For detailed information about tuning Liquid Data performance, see Tuning Performance in Deploying Liquid Data.