Aleks,
You ask a great Data Preparation question. Let's break your question down so we can get you the answers you are looking for.
Yes, if you are on a Viya 3.5 or an older Viya 4 version that still has Data Studio enabled, you certainly can go to Data Studio (Prepare Data) and add a new column. You would do that by selecting the Calculated Column Transformation and adding it to your plan. When that transformation is open in your Plan, select the Create new column radio button and then pick the appropriate options for the name of the column, type, length, label, and format. If you know what you are adding to that column you can add that content or code in the code pane. If you are simply needing a new column with no content, you can simply add a set of single quotes with a space (' ').
In Data Studio you also have the ability to use the code node to programmatically add a new column.
In SAS Studio, which is where we are moving data preparation capabilities for SAS Viya 4 users, you will be able to use either the Manage Columns step or the Calculate Columns step to create a new column in a flow. You would simply add the desired step and then in the step properties click on the New button to add that new column. When you click on the new button it will bring up an expression builder asking for the name, label, type, length, format, and informat of the new column to create. Both steps use the same expression builder.
In SAS Studio, you will also be able to use the code node to programmatically add a new column.
Data Studio SAS Studio Flows
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