Remove duplicates from collection

Use the Remove duplicates from collection action A tool for building the processes, logic, and direction within workflows. to search for and remove any values that exist more than once in the collection A variable containing multiple items, such as email addresses. Collection variables are useful for storing and operating on query results. For example, you can set up collection variables for names, email addresses, and index values to store results from querying a list. You can then loop through items in a particular collection variable (names, emails, or index values)., leaving only one instance of each value.

For example, you might want only unique city values from a list.

To learn more about collection actions, complete the Nintex for Office 365 - Collection Operations course on Nintex University.
Before you start 

Variables are placeholders that store information that changes each time the workflow runs or even during execution of a single workflow instance.

Each variable has a type that determines what values can be stored in the variable, such as a date, number, file path or a workflow user name. For example, if you want to save the name of an employee in a variable, you have to create a variable of type Text. The workflow can then store a name of the employee, such as "John," in the variable.

  • Text: Text string.
  • Boolean: Yes or No value.
  • Date/Time: Date and time value.
  • GUID: Globally unique identifier, often used to reference a list item in SharePoint.
  • Number: Integer number with decimal value.
  • Integer: Integer number with no decimal value.
  • Choice: A value that requests a selection from a list of allowed values.
  • Person or Group: A value that requests a selection from a user lookup.
  • Hyperlink: A value that requests a hyperlink URL and description.
  • Dictionary: A container that holds a single logical unit of variables. For more information, see Dictionary variables.
  • Collection: An index-based array of values, also known as an ordered list of values. For more information, see Collection variables.

In NintexOffice 365, the different categories of variables that can be used in a workflow are given below:

  • Start Variables: Workflow variables with the initiation option selected. Start Variables are used to get data from users when a workflow manually starts.

    • For more information on manually starting a workflow, see .

You can insert an existing Workflow Variable or Context Variable into the configuration fields of workflow actions A tool for building the processes, logic, and direction within workflows. and you can create user-defined variables for use throughout your workflow.

You can create user-defined variables from the Action configuration window when you are configuring a workflow action or from the toolbar of the designer page.

  1. In the Action configuration window, click in a field that accepts variables.
  2. Do one of the following depending on the method available;
    • On the drop-down list that appears, Click Create New Variable.
    • On the Insert Reference pane that appears, expand the Workflow Variables section and click Create New Variable.
  3. Do the following in the Workflow Variables pane to create the variable:
    1. For Name, type the variable name you want to use.
    2. Select a Type.
    • If you want to display the variable on the start form, select the Show on start form check box.
    1. Click Create.
  1. On the toolbar of the Designer page, click Variables. The Variables dialog box appears.
  2. Click New and fill in the following:
    1. For Name, type the variable name you want to use.
    2. For Type, select a variable type corresponding to the type of data you want to store.
    1. Click Save.

For more information, see User-defined variable types and Initiation options.

The following table describes the variable types available in the Variables dialog box as well as their initiation options, which are available when you select Yes for Initiation. Initiation options control the display and behavior of the variable on the start form that is displayed when a workflow is started manually.

Variable type Description

Initiation Available

 Initiation options
Text

Any text value.

Underlying .NET data type: System.String.

Yes
  • Multiple Lines: When selected, allows multiple text lines in the default value.
  • Description: Text to display under the text box on the start form. Example: "Enter new name".
  • Default value: Default value for variable.
Boolean

Yes or No value.

Underlying .NET data type: System.Boolean.

Yes
  • Description: Text to display under the check box on the start form. Example: "Enable?"
  • Default value: Default value for variable: Yes (true) or No (false).
Date/Time

Date and time value.

Underlying .NET data type: System.DateTime.

Yes
  • Description: Text to display under the text box on the start form. Example: "Select the date needed by".
  • Default value: Default value for variable: None or Today's date.
  • Allow blank values?: When selected, allows the start form to be submitted without specifying a value for the variable.
  • Display format: Display format for variable: Date and time or Date only.
GUID

Globally unique identifier, often used to reference a list item in SharePoint.

Underlying .NET data type: System.Guid.

No

 (n/a)
Number

Numeric with a Decimal value.

Underlying .NET data type: System.Double.

Yes
  • Description: Text to display under the text box on the start form. Example: "Specify quantity".
  • Default value: Default value for variable. Can be selected or entered.
Integer

Numeric without a decimal.

Underlying .NET data type: System.Int32.

No

 (n/a)
Choice

A value that requests a selection from a list of allowed values. The value selected by the workflow initiator is stored in the variable.

Underlying .NET data type: System.String.

Yes
  • Description: Text to display under the drop-down list on the start form. Example: "Select the product"
  • Choices: Choices available in the variable. Enter each choice on a separate line.
  • Default value: Default value for variable. Enter one of the specified choices.
Person or Group

A value that requests a selection from a user lookup. The item selected by the workflow initiator is stored in the variable.

Underlying .NET data type: System.String.

Yes
  • Description: Text to display under the text box on the start form. Example: "Select your manager"
  • Allow selection of: Scope of allowed selection: People Only or People and Groups.
  • Choose from: Source of selection: All Users or SharePoint Group. Use the drop-down list to select a SharePoint group.
  • Allow blank values?: When selected, allows the start form to be submitted without specifying a value for the variable.
  • Allow multiple values?: When selected, allows entry of multiple values.
Hyperlink

A value that requests a hyperlink URL and description.

Two text boxes are provided: 

  • Type the Web address
  • Type the description

The values entered by the workflow initiator are stored in the variable.

Underlying .NET data type: System.String.

Yes
  • Description: Text to display under the "Type the description" text box on the start form. Example: "Enter a display value for the URL"
  • Allow blank value?: When selected, allows the start form to be submitted without specifying a value for the variable.
Dictionary

A container that holds a single logical unit of variables. For more information, see Dictionary variables.

Underlying .NET data type: Microsoft.Activities.DynamicValue.

No

 (n/a)

Collection

An index-based array of values, also known as an ordered list of values. For more information, see Collection variables.

No

(n/a)

You can insert a Workflow Variable, Reference A workflow reference which is used to construct content containing information specific to the list or library item and to the current instance of the workflow. or a Context Variable into the configuration fields of workflow actions A tool for building the processes, logic, and direction within workflows..

Each field that accepts variables accepts one or more methods for inserting variables. The method available differs depending on the field.

Available methods are given below:

  • Click on the field and select an existing variable from the drop-down list for the field.

  • Click on the field, click Create New Variable, and fill the following fields in the Workflow Variable pane that appears:
    1. For Name, type the variable name you want to use.
    2. Select the Show on start form check box if you want to display the variable on the start form.
    3. Click Create.
  • Click on the field, select Workflow Variables or Workflow Context, and select a variable from the corresponding drop-down list.

  • Click Advanced Lookup, select Workflow Variables or Workflow Context from the drop-down list that appears, and then select a variable from the corresponding drop down and click Insert.

  • Click on the field that accept references and from the Insert Reference pane that appears on the right, double-click on a reference to select. Available sections and lookup values depend on the options available for the workflow action.
    Section Description
    Item Properties

    Metadata columns for the item the workflow is associated with. Available only for list workflows.
    Workflow Context

    Context variables that represent data related to the current workflow instance, such as current item or site URL and workflow name.

    • Current item URL: The URL of the item the workflow is associated item. Available only for list workflow actions.
    • Current site URL: The URL of the site the workflow is associated site.
    • Initiator login name: The login name of the person who started the workflow instance.
    • Initiator display name: The display name of the person who started the workflow instance.
    • Initiator email address: The email address of the person who started the workflow instance.
    • Instance ID: The unique identifier of the workflow instance.
    • List ID: The unique identifier of the list the workflow is associated with. Available only for list workflow actions.
    • List Name: The name of the list the workflow is associated with. Available only for list workflow actions.
    • Manager login name: The login name of the manager of the initiator (the person who started the workflow instance).
    • Manager display name: The display name of the manager of the initiator (the person who started the workflow instance).
    • Manager email address: The email address of the manager of the initiator (the person who started the workflow instance).
    • Publish user: The person who published the workflow.
    • Workflow name: The name of the executing workflow.
    Workflow Variables Workflow variables configured for the workflow.

You can configure variables to collect data when a workflow is manually started. These variables will be shown on a start form used to initiate the workflow and allows users to specify a value for the workflow variable before the workflow starts, basically passing values into the workflow before it starts.

Variables displayed on a start form are also known as the "start data" of the workflow and represent data that must be collected when the workflow is started.

Note:  If the workflow starts automatically, then default values are used for start data.

To learn how to manually start a workflow, see Start a workflow manually.

Configure a variable to show on a workflow start form:

  1. Open the required workflow. The workflow designer opens.

  2. On the toolbar, click Variables. The Variables window opens.

  3. To edit an existing variable, click the required variable. The row becomes editable.

    or

    4. To create a variable, click New on the Variables window toolbar, enter a Name, and select the Type for the variable.

  4. Select the Initiation check box for the required variable.
  1. Click Save to commit changes.

Add and configure Remove duplicates from collection action

In the Designer:

  1. Click the Operations action group in the action toolbox.

    2. or

    Type the action name or function in the Search field at the top of the action toolbox.

  1. Drag the Remove duplicates from collection action to the point in the workflow when you want to remove duplicate items from a collection.
  2. Open the Action Configuration window. For steps on how to open the Action configuration window, see Action configuration window
  1. Select a Target Collection.
  2. Select an output variable.
  3. Click Save.

For more information on the fields and buttons see, Remove duplicates from collection, buttons and settings.

Field

Description
Target collection

Collection variable that you want to remove duplicates from.

Output

Collection variable to store the collection with the duplicate items removed.

For more information about how to use Lookups in configuration fields, see Lookups in action configuration fields.