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Resources and Shifts
Phase II: Organizing resources
Create a string attribute
In the original Final Car Wash model, the preference for washing only or for washing and waxing is set as a string attribute named Preference. By pointing to either row 1 or 2 in a table in the Executive’s Item Attri- butes tab (shown at the immediate right) the attri- bute routes cars to the cor- rect bay.
String values table in Executive block’s Item Attributes tab
As you will see below, the two new resource requirements (Wash Requirement and Wash/Wax Requirement) are in records 4 and 5, respectively, of the database’s Requirements table, shown above right.
This section shows how to create a new string attribute that points to records 4 and 5 in the database table. The goal is to link the Executive’s string values table to the database’s table of resource requirements. This will give the Resource Manager a mechanism to point to the records that contain the resource requirements for the model.
☞ An alternative method would be to use a Lookup table as is done in the Auto Club Emergency Service model located at \Examples\Discrete Event\Resources and Shifts\Advanced Resources
When the string attribute is changed, settings in the following blocks must also be changed to use the new attribute:
• Set
• RandomNumber • Queue
• Select Item Out
☞ These changes are only necessary because the attribute needs to be changed. If the model had been originally constructed to use the ARM system, there would be no reason to make these changes.
Set block
In this model, the attribute is set in the Set block (Set Attribute). In the block’s dialog:
In the Property Name column, select the Preference cell to open the popup menu
From the list of properties, select New String Attribute
Name the new attribute Requirements and click OK. This opens the Executive block’s Item Attributes tab. The string values table on the right is now named Requirements.
In the string values table (Requirements), click the Link button to open the Link dialog Choose Link To: Database Table
Select the database named Advanced Resources and click OK
Choose Table Name: Resource Requirements. This displays a table listing all the resource requirements that have been created for this model.
Resource Requirements table
of Advanced Resources database
Discrete Event

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