When using values from a file, VuGen lets you specify the way in which you assign data from the source to the parameters. The following methods for assigning data are available:
Assigns data to a Vuser sequentially. As a running Vuser accesses the data table, it takes the next available row of data.
If there are not enough values in the data table, VuGen returns to the first value in the table, continuing in a loop until the end of the test.
Assigns a random value from the data table every time a new parameter value is requested.
When running a scenario in LoadRunner, or a script in HP Business Process Monitor, you can specify a seed number for random sequencing. Each seed value represents one sequence of random values used for test execution. Whenever you use this seed value, the same sequence of values is assigned to the Vusers in the scenario. You enable this option if you discover a problem in the test execution and want to repeat the test using the same sequence of random values.
Assigns a unique sequential value to the parameter for each Vuser. Ensure that there is enough data in the table for all Vusers and their iterations. If you have 20 Vusers and you want to perform 5 iterations, your table must contain at least 100 unique values.
If you run out of unique values, VuGen behaves according to the option you select in the When out of values field. For more information, see Parameter Properties Dialog Box.
Note: For LoadRunner users: If a script uses Unique file parameterization, running more than one Vuser group with that script in the same scenario may cause unexpected scenario results. For more information about Vuser groups in scenarios, see the Function Reference.
For details on the different data assignment and update methods, see Data Assignment and Update Methods for File/Table/ XML Parameters.
For details on how parameters behave when the number of iterations do not match the number of values in the parameter file, see Vuser Behavior in the LoadRunner Controller.