Aqua 2023.3 Help

Virtual columns

A virtual column is an IDE virtual object that contains values calculated using the data of other columns. It is not defined in the database code, and it cannot be used to create indexes. The data of the virtual column is not stored in the database.

For example, to have a column that would contain data from both first_name and last_name columns, create a virtual column with the following expression: first_name || '.' || last_name.

The virtual column with your expression result will appear in the table, and it will also be available in the Database tool window as a virtual object.

Virtual column

The expression used to calculate values for virtual column is stored in external-data-<data_source_name>.xml. You can select another name for the XML file and other place to store this file. To change or see the path to the XML document, open data source settings by pressing Command I, click the Options tab and see the Virtual objects and attributes field.

Virtual columns can be seen in the Database tool window. You can see a reference on node and object icons in the Data sources and their elements chapter of Database tool window topic.

For the table column icons, refer to Possible icon combinations for columns.

Create a virtual column

  1. In the Database tool window ( View | Tool Windows | Database) , expand the data source tree until the nodes of tables.

  2. Right-click the table node and select New | Virtual Column.

  3. In the Modify dialog that opens, enter the name of your virtual column in the Name field.

  4. Type your expression in the Expression field.

  5. Click OK.

  6. If the Save external data for <data_source_name> dialog opens, specify the directory for external-data-<data_source_name>.xml file and click Save.

Create a virtual column
Last modified: 19 October 2023