Input and output data for operations

Most operations in a process take input data, process the data or perform some action based on the data, and then return data as output. You configure operation properties to specify the input data and the location to store the output data. Typically, the properties are organized in Input and Output property groups in the Properties view. For some operations, other property groups are used.

The operation determines the type of data that you need to use for a property value. The operation can also allow you to specify the value in different formats.

Format	Description	Suggested use
Literal value	The property value is specified by typing the value in a text box, or using a drop-down list on the Properties view.	The value is used for only one operation property in the process. If values are used several times, you can use variables or XPath expressions to save time re-entering the same value.
Template	The data is specified as a string with embedded XPath expressions, where the expressions are wrapped in `{$...$}` symbols. (See Specifying template expressions.)	The operation property requires a string value, and the value contains both static text, and text that changes depending on the process instance. For example, this format can be used when providing task instructions. (See Providing task instructions.)
Variable	The data is specified as a variable that you select from a list. The value that the variable stores is used as the property value. (See Process variables.)	The value is already stored in a variable: The value is passed into the process when the process is invoked. You create the variable and set the value explicitly.
XPath expression	The data is specified by an XPath expression, which you can construct using the XPath Builder dialog box. (See Creating XPath expressions.)	The value is stored in the process data model and you want to specify either the entire variable value, or a subset of the variable data. For example, you use XPath Expressions to specify the value of a specific item of data from a submitted form. (See Retrieving form field values.)

Typically, specifying the literal value of a property is easier to accomplish than using a variable. However, specifying a variable as the property value is recommended in the following situations:

The value is passed into the process as a process invocation parameter and stored in a variable.
An operation returns the value and it is stored in a variable.
You use the same value for the property of several operations in the process.

Input and output data for operations

See also