Creo Options Modeler > References > Fundamentals > Relations and Parameters > Restricted Value Parameters > About Table-restricted Parameters
  
About Table-restricted Parameters
You can use tables with conditional values to create restricted parameters. These values use definitions from an external definition file. Using the restriction table, you can define sets of restricted parameters whose values are mutually conditional. The table-restricted parameters are added in sets and not individually. The first column in the restriction table contains labels that describe each table set or row. If you select any set or row in the restriction table, all parameters including those with Null values are automatically created. You can use the special word NULL to assign a null value or no value to a parameter.
A parameter that describes an entire set of parameters and their values is called a set label parameter. A restriction table must have only one set label parameter and its values must be unique. You can have multiple tables with similar set label parameter values. The set label parameters are displayed in the Parameters dialog box. These parameters can be driven from Family Tables and Program.
A restriction definition file can refer to multiple restriction tables and the same parameter name can appear in several tables. However, you cannot add a parameter set to an object such as feature, part, or assembly if the parameter set contains a parameter whose name matches with that of a parameter that already exists and belongs to the same object.
The restriction definition file uses the following format to define parameters for a restriction table:
{
Name = <name>

Type = <type> (the basic type - integer, real, string, boolean, etc.)

[Access=<access>]

TABLE = <table-name_1>, <table-name_2>, .., <table-name_n>

}
Where <table-name_1>, <table-name_2>, …, <table-name_n> are the names of tables that contain values for the given parameter.