Using the Data Model Editor

What Is a Data Model?

A data model is an object that contains a set of instructions for BI Publisher to retrieve and structure data for a report. Data models reside as separate objects in the catalog.

At the very simplest, a data model can be one data set retrieved from a single data source (for example, the data returned from the columns in the employees table). A data model can also be complex, including parameters, triggers, and bursting definitions as well as multiple data sets.

To build a data model, you use the data model editor.

Components of a Data Model

A data model supports the following components:

• Data set

  A data set contains the logic to retrieve data from a single data source. A data set can retrieve data from a variety of data sources (for example, a database, an existing data file, a Web service call to another application, or a URL/URI to an external data provider). A data model can have multiple data sets from multiple sources.

• Event triggers

  A trigger checks for an event. When the event occurs the trigger runs the PL/SQL code associated with it. The data model editor supports before data and after data triggers as well as schedule triggers. Before data and after data triggers consist of a call to execute a set of functions defined in a PL/SQL package stored in an Oracle database. A schedule trigger is executed for scheduled reports and tests for a condition that determines whether or not to run a scheduled report job.

• Flexfields

  A flexfield is a structure specific to Oracle Applications. The data model editor supports retrieving data from flexfield structures defined in your Oracle Application database tables.

• Lists of values

  A list of values is a menu of values from which report consumers can select parameter values to pass to the report.

• Parameters

  A parameter is a variable whose value can be set at runtime. The data model editor supports several parameter types.

• Bursting Definitions

  Bursting is a process of splitting data into blocks, generating documents for each data block, and delivering the documents to one or more destinations. A single bursting definition provides the instructions for splitting the report data, generating the document, and delivering the output to its specified destinations.

• Custom Metadata (for Web Content Servers)

  If you have configured a Web content server as a delivery destination and enabled custom metadata, then the Custom Metadata component displays in the data model editor. Use this component to map data fields from your data model to the custom metadata fields set up for a set of Rules defined in a Content Profile.

Features of the Data Model Editor

Use the data model editor to combine data from multiple data sets from different data sources, such as SQL, Excel files, Web services, HTTP feeds, and other applications into a single XML data structure. Data sets can either be unrelated or a relationship can be established between them using a data link.

The data model editor enables you to perform the following tasks:

• Link data — Define master-detail links between data sets to build a hierarchical data model.

• Aggregate data — Create group level totals and subtotals.

• Transform data — Modify source data to conform to business terms and reporting requirements.

• Create calculations — Compute data values that are required for your report that are not available in the underlying data sources.

About the Data Source Options

BI Publisher supports a variety of data source types for creating data sets. These can be categorized into three general types:

The first type are data sets for which BI Publisher can retrieve metadata information from the source. For these data set types, the full range of data model editor functions is supported. These data set types are:

• SQL queries submitted against Oracle BI Server, an Oracle database, or other supported databases

  See Creating a Data Set Using a SQL Query.

  For information on supported databases, see "System Requirements and Certification" in the Oracle Fusion Middleware Data Modeling Guide for Oracle Business Intelligence Publisher.

• Multidimensional (MDX) queries against an OLAP data source

  See Creating a Data Set Using a MDX Query Against an OLAP Data Source.

• Queries against your LDAP repository to retrieve user data

  You can report on this data directly, or join this to data retrieved from other sources. See Creating a Data Set Using an LDAP Query.

• Microsoft Excel spreadsheet data sources

  The Excel spreadsheet can be either stored in a file directory set up as a data source by your administrator; or you can upload it directly from a local source to the data model. See Creating a Data Set Using a Microsoft Excel File.

• XML data file data sources

  The XML file can be either stored in a file directory set up as a data source by your administrator; or you can upload it directly from a local source to the data model. See Creating a Data Set Using a XML File.

• CSV (comma separated value) file data sources

  The CSV file can be either stored in a file directory set up as a data source by your administrator; or you can upload it directly from a local source to the data model. See Creating a Data Set Using a CSV File.

For the second type, BI Publisher can retrieve column names and data type information from the data source but it cannot process or structure the data. For these data set types, only a subset of the full range of data model editor functions is supported. These data set types are:

• Oracle BI Analyses

  See Creating a Data Set Using an Oracle BI Analysis.

• View objects created using Oracle Application Development Framework (ADF)

  See Creating a Data Set Using a View Object.

For the third type, BI Publisher retrieves data that has been generated and structured at the source and no additional modifications can be applied by the data model editor. These data set types are:

• HTTP XML feeds off the Web

  See Creating a Data Set from an HTTP XML Feed.

• Web services

  See Creating a Data Set Using a Web Service.

  Supply the Web service WSDL to BI Publisher and then define the parameters in BI Publisher to use a Web service to return data for the report.

Process Overview for Creating a Data Model

Table 13-1 lists the process overview for creating a data model.

Launching the Data Model Editor

Launch the data model editor from the BI Publisher global header or Home page in one of the following ways:

To launch the Data Model Editor from the global header:

1. Click New and then click Data Model to open the data model editor.

To launch the Data Model Editor from the Home page:

1. Under the Create region, click Data Model.

The Data Sets page is the default page displayed as shown in Figure 13-2.

Figure 13-1 Data Sets Page

About the Data Model Editor Interface

The data model editor is designed with a component pane on the left and work pane on the right. Selecting a component on the left pane launches the appropriate fields for the component in the work area.

The data model editor toolbar, shown in Figure 13-2, provides the following functions:

Figure 13-2 Data Model Editor Toolbar

• Manage Private Data Sources — Launches the Manage Private Data Sources dialog to create a private data source connection for use in SQL data sets.

• View Data — Displays the Data tab where you view and generate sample data.

• Create Report — Launches the Report Wizard to create a report and automatically populates the Data Model field with the current data model name.

• Save / Save As — Select Save to save your work in progress to the existing data model object or select Save As to save the data model as a new object in the catalog.

• Help —View online help for the data model editor.

Setting Data Model Properties

To access the Data Model Properties page as shown in Figure 13-3, click the Data Model node in the components pane.

Figure 13-3 Data Model Properties

Enter the following properties for the data model:

Description —  The description that you enter here displays in the catalog. This description is translatable.

Default Data Source — Select the data source from the list. Data models can include multiple data sets from one or more data sources. The default data source you select here is presented as the default for each new SQL data set you define. Select Refresh Data Source List to see any new data sources added since your session was initiated.

Oracle DB Default Package — If you define a query against an Oracle database, then you can include before or after data triggers (event triggers) in your data model. Event triggers make use of PL/SQL packages to execute RDBMS level functions. For data models that include event triggers or a PL/SQL group filter, you must enter a default PL/SQL package here. The package must exist on the default data source.

Database Fetch Size — Sets the number of rows fetched at a time through the JDBC connection. This value overrides the value set in the system properties. If neither this value nor the server setting is defined, then a default value of 100 is used. If the server property Enable Auto DB fetch size mode is set to True, this value is ignored.

For more information, see "Setting Data Engine Properties."

Query Time Out - applies to SQL query-based data models. If the SQL query is still processing when the time out value is met, the error "Failed to retrieve data xml." is returned. Enter a value in seconds. If you do not enter a value for this data model, the server property value is used. For information about the server setting, see "Setting Data Engine Properties."

Scalable Mode — Processing large data sets requires the use of large amounts of RAM. To prevent running out of memory, activate scalable mode for the data engine. In scalable mode, the data engine takes advantage of disk space when it processes the data. Setting this to On will impact performance, but guard against out of memory errors.

Note that Enable Data Model Scalable Mode is also a server level property therefore by default the data model-level property is set to Instance Level to inherit the server or instance level setting. To turn scalable mode on or off for this particular data model, select On or Off from the list.

For information about the server level setting, see "Setting Data Engine Properties."

SQL Pruning - applies to Oracle Database queries only that use Standard SQL. If your query returns many columns but only a subset are used by your report template, SQL pruning returns only those columns required by the template. Setting this property enhances processing time and reduces memory usage.

Note that Enable SQL Pruning is also a server level property therefore by default the data model-level property is set to Instance Level to inherit the server or instance level setting. To turn SQL pruning on or off for this particular data model, select On or Off from the list.

For information about the server level setting, see "Setting Data Engine Properties."

Backup Data Source — If you have set up a backup database for this data source, select Enable Backup Connection to enable the option; then select it when you want BI Publisher to use the backup.

• To use the backup data source only when the primary is down, select Switch to Backup Data Source when Primary Data Source is unavailable. Note that when the primary data source is down, the data engine must wait for a response before switching to the backup.

• To always use the backup data source when executing this data model, select Use Backup Data Source Only. Using the backup database may enhance performance.

Attachments to the Data Model

The Attachment region of the page displays data files that you have uploaded or attached to the data model.

Attaching Sample Data

After you build your data model, you must attach a small, but representative set of sample data generated from your data model. The sample data is used by BI Publisher's layout editing tools. Using a small sample file helps improve performance during the layout design phase.

The data model editor provides an option to generate and attach the sample data. For more information, see Testing Data Models and Generating Sample Data.

The administrator can set a limit to the size of the sample data file. For more information, see "Setting Data Engine Properties."

Attaching Schema

The data model editor enables you to attach sample schema to the data model definition. The schema file is not used by BI Publisher, but can be attached for developer reference. The data model editor does not support schema generation.

Data Files

If you have uploaded a local Microsoft Excel, CSV, or XML file as a data source for this report, the file displays here. Use the refresh button to refresh this file from the local source. For information on uploading files to use as data sources, see Chapter 14, "Creating Data Sets".

Figure 13-4 shows the Attachments region with sample data and data files attached:

Figure 13-4 Attachments Region with Attached Sample Data and Files

Managing Private Data Sources

Data model developers can create and manage private JDBC, OLAP, Web service, and HTTP data source connections without having to depend on an Administrator user. However, Administrator users can still view, modify, and delete private data source connections, if needed.

To create a private data source connection:

1. From the data model editor toolbar, click Manage Private Data Sources.

2. Select the connection type tab, and click Add Data Source as shown in Figure 13-5.

   Figure 13-5 Creating Private Data Source Connections

   
   
   
   

   Note: If you are logged in as an Administrator, all data source connections will display for you in this dialog; however, you can only create or modify JDBC, OLAP, HTTP, and web service data sources from this dialog.

   
   

3. Enter the private connection name, and the required fields.

4. Click Test Connection. A confirmation is displayed.

5. Click Apply. The private data source connection is now available for use in your data sets.

Private data source connections are identified by the word (Private) appended to the end of the data source name. For example, if you create a private JDBC connection called My JDBC Connection, it is displayed as My JDBC Connection (Private) in the data source drop-down lists.

If your user has the Administrator role, you can only create public data sources, even if you create the data source from the Manage Private Data Sources page. For more information about private data source connections, see "About Private Data Source Connections."

For more information on setting up the data source types, see "Setting Up Data Sources."