When we talk about a column, we mean a field in your original dataset, as imported into your Bunker.

During the process of normalisation, the data in columns is converted to categories or keys. The original columns are then deleted, safeguarding the security of your source data.

In an activation Bunker - a special type of Bunker used for queries which can identify individuals - you can alternatively choose to retain one or more columns in their original form. For more information on this, see output column.