VI Concat Process Object

The Visual Integrator (VI) Concat process object brings columns from multiple sources into the data flow input. If a column is requested in the output flow that does not appear in all the input flows, the value of that output column is null in the appropriate rows.

VI Concat Process Object icon

The Concat process object concatenates multiple input flows and passes a union of the input columns into the data flow.

The Concat process object has Closedthree panes where you set attributes.

VI Concat All Panes

You set attributes for the Concat process object in the Closedobject attributes pane.

VI Concat Object Attributes

Attribute Description
Input

Defines the objects from which the data flow arrives. Use one of the following methods to attach the Concat object to an input data flow object.

  1. Place two or more input objects on the task flow, and specify attributes for each input object.

  2. Right-click one of the input objects, and click ClosedNew Object after this > Process > Concat.

    VI Concat - choose concat

    The first input object is Closedattached to the Concat process object.

    VI Concat 1st connection

  3. Click the output node on the next input object, and attach it to the Concat object's input node.

    Two input objects are now Closedattached to the Concat process object.

    VI Concat 2nd Input

    The ClosedInput attribute is populated with a list of the input objects.

    VI Concat Input listing

  4. Repeat for any additional input objects.

  1. Place a Concat process object and two or more input objects on the task flow. Specify attributes for each input object. ClosedFor example:

    VI Concat Items placed

  2. With the Concat object selected, click its Input attribute's browse button, and move the pointer to the task flow.

    Note that a Closeddotted-line connector is attached to the Concat object.

    VI Concat - attaching from concat 1

  3. Attach this connector to one of the input objects, and repeat step 2 to attach additional input objects. ClosedFor example:

    VI Concat - attaching 2nd from concat

    The ClosedInput attribute is populated with a list of the input objects.

    VI Concat Input listing

Change_Inputs_Order

Specifies the order of input processing. Defaults to the order that input objects were attached to the Concat process object.

  1. Click the Change_Inputs_Order attribute's browse button.

    The ClosedReorder Items dialog box opens.

    VI Concat - Reorder Items dialog

  2. Select an input, and use the arrows to adjust the order.

    NOTE: You can click the Remove icon to remove inputs from the Concat object.

  3. Click OK.

Each object has an area where you can enter comments.

It is a DI best practice to enter a note for every object in a VI script. You can set a VI preference to give a warning for each object without a note. For more information, see Visual Integrator Preferences.

ClosedConcat object with comments

VI Concat Object Comments

The ClosedConcat object column grid displays the columns from the input data flow.

VI Concat Column Grid

Attribute Description
Input Column

Displays the name of each input column. This attribute is read-only.
Source Object

Displays the name and object type of the source object. Double-click the Source Object for a column to change the task flow focus to that object.

With the following input flows:

Input A:

Example of input A for VI Concat process object

Input B:

Example of input B for VI Concat process object

You get the following concatenated output:

Example output from VI Concat process object