About Multi-Source Session Variables

Create and use multi-source session variables when you need a variable to provide values from more than one data source. You can use multi-source session variables in data filters and expressions.

There is no restriction to the number of values that the multi-source session variable can hold.

In a session initialization block, you use the following format to create a session variables for each source. This format contains four underscore characters as the separator between the variable name and the source.

<ms_variable_name>____<source>

The multi-source system variable definitions that you created are listed in the saved session initialization block's definition (for example, MVCOUNTRY____ORCL and MVCOUNTRY____SNFL). But when you create expressions that include the multi-source session variable name, the Expression Editor's Variables tab displays the variable name (for example, MVCOUNTRY).

For an example of how to create multi-source session variables, see Create a Multi-Source Session Variable.

You can add values to the multi-source session variable from other component initialization blocks that return values. The multi-source session variable fails if all of the component initialization blocks return null values.

You can set processing dependencies and deferred processing for multi-source session variables, similar to regular session variables.