Option Pack › Creating Policies with Policy Xpress › Create a Policy › Data Elements

Data Elements

Data elements are the core of policy rules and are also used for creating other policy data. Data elements represent the information used when defining a policy. A policy can contain multiple data elements.

Policy Xpress uses flexible plug-ins for gathering the data element information. Each one of the plug-ins can do a small scale, dedicated task. However, several plug-ins can be used together to build more complex policies. An example of a data element plug-in is a user attribute element. The goal of the element is to gather information about a certain attribute which is a part of the user's profile.

Data elements are calculated when they are called, meaning either a rule is using the data element, or another element needing calculation is using the data element as a parameter.
For example, an SQL query data element can retrieve a value from a table, but it needs the user's department to build the query. In this case, the department data element must run before the SQL query data element, and then the value can be used as a parameter.

The following fields define a data element:

• Name

  Defines a friendly name that describes the data element. Some data elements are complex (such as getting variables or retrieving information from the database). Be sure to select a meaningful name to simplify data element management.

• Category

  Provides a grouping of data elements. This field sorts the data elements and makes selection easier.

• Type

  Specifies the data element type, each with its own dedicated use. This field is based on the category selected.

• Sub type

  Defines possible variations of the same data. Most data elements only support the Get function.

  For example, the user attribute data element has the following sub types:

  • Get—returns the values of the attribute
  • is multi valued—returns true if the value is multi-valued
  • is logical—returns true if the value is logical
• Explanation and Description

  Provides a prepopulated description of the sub type. Each sub type option selected provides a different description to help in understanding its function and what the expected values are.

• Parameters

  Defines the parameters passed to the data element. Data elements are dynamic and can do different things based on the parameters. A user attribute data element returns different results based on the attribute selected. The sub type option also defines the number of parameters, their names, and the optional values when available.

  You can add additional parameters if necessary. The SQL query example accepts two required parameters, the data source and the query itself. The query can use the "?" to be replaced with values (much like a prepared statement). Adding additional parameters allows you to set those values.