Creating a variable

A variable is used to store a value. You can use the variable throughout your Flow; for example, while creating a record, performing an update, or with delete operations.

Here is business scenario: Robby Williams is working as a system administrator for Universal Containers. Currently, he is developing a Visual Workflow and wants to create a variable to store customer names.

To create a variable in your Flow, follow these instructions:

1. Navigate to Setup | Build | Create | Workflow & Approvals | Flows.
2. Click on the New Flow button; it will open the Flow canvas for you.

1. Navigate to the Resources tab and double-click on the Variable option that is available under the CREATE NEW section, as shown in the following screenshot:
   
   
   This will open a window for you, where you have to enter the following details:
   • Unique Name: Enter a unique name. The name must begin with a letter, and use only alphanumeric characters and underscores. Uniqueness applies only to elements within the current Flow. In this case, enter VarTCustomerName.
   • Description: Write some meaningful text so other developers/administrators can easily understand why this variable has been created. When you select the Variable in the Explorer tab, then this description appears in the Description pane.
   • Data Type: This determines which types of value a variable can store. Select the data type of Text. The following are the available data types for a variable:
     • Text: This is used to store any combination of letters and numbers.
     •  Number: This is used to store any numbers.
     • Currency: This is used to store currency.
     • Date: This is used to store the date.
     • DateTime: This is used to store the date with the time.
     • Boolean: This is used to store either true or false.
     • Picklist: This is used to store picklist values. It supports the ISPICKVAL() function in Flow formulas.
     • Picklist (Multi-select): This is used to store multi-select picklist values.
   • Scale: This is only available when the data type is set to Number or Currency. Scale is the number of digits to the right of the decimal point.
   • Input/Output Type: This defines whether a variable is available within the Flow or can also be accessed outside the Flow. The different input/output types are as follows:
     • Private: This variable can be allocated and used only within the Flow.
     • Input Only: This allows you to set a variable at the start of the Flow using Visualforce controllers, URL parameters, or subflow inputs.
     • Output Only: This means that you can access a variable's value from Visualforce controllers and other Flows.
     • Input and Output: This means that you can set a variable's value at the start and access its value outside the Flow. In our case, select Input and Output.
     • Default Value: This allows you to set a default value for the variable. You can either manually enter the value or use the drop-down list to assign the value of a Flow resource as the default. In our case, select {!$GlobalConstant.EmptyString} available under GLOBAL CONSTANT. This will look like the following screenshot:

4. Once you are done, click on the OK button.