When information must come from a VDB group that has been generated, the substitution expressions that access a VDB data group makes this information available within a webject even though the exact value is not known at the time the task is being designed.

You can use substitution expressions in any data attribute value on a param tag.

To specify one parameter value that is substituted from a VDB data group, the parameter value can be similar to the following:

Use grp_name[] in these formats when there is only one element (row) in the group named “grp_name.” Use att_name[] in these formats when there is only one value in the att_name attribute. If the data group has more than one element, you can use grp_name[0] to access the first element in the group and use grp_name[N] to access the last element in the group. To access other elements, you can specify the index of the element inside the brackets. Similarly, you can use 0, N, or other indices inside the brackets to access a specific value in the attribute named by att_name[].

To specify multiple parameter values as input, you include the asterisk (*) as the value selector. To format multiple parameter values correctly, you must also include the delim attribute to identify the comma as the separator in the string that is substituted. For multiple values, the parameter value can be similar to the following:

The asterisk in the value selector, [*], selects all values and concatenates them together into a string using the comma as a separator. The delim attribute tells the webject that multiple values in the data attribute are separated by a comma.

The last set of formats assumes that there is only one element in the named group. If the data group has more than one element, you can use grp_name[0] to access the first element in the group and use grp_name[N] to access the last element in the group. To access other elements, you can specify the index of the element inside the brackets.

For more information, see General Value Substitution Syntax.

Assume that the following table represents the elements (rows), attributes (column headings) and attribute values (cells in columns) in the “EMP” VDB group:

You can create a new group called “salesEmp” by adding the DEPT attribute column to the “EMP” group using substitution in the following Create-Group webject:

After substitution processing by Info*Engine, the parameters in the webject are as follows:

Executing the Create-Group webject creates the “salesEmp” group that is represented by the following table: