Join a data table to a geographic layer

With the CartoVista Server, you can import data tables and attach them to your geographic layers. All you need to do is use a Unique Identifier that is the same for both files.

Learn how to:

ℹ️   Check out this article to manage time-based one-to-many joins

Perform a join on the Server

To see which data types are supported by the CartoVista Server, click here.

     1. Import your Geographic Layer and your Data Table into the CartoVista Server. To find out how to do this, click here.

     2. You can prepare your database by changing the field names or the data type. To find out how to do this, click here.

     3. To attach a Data Table to a Geographic Layer you need to define the Unique Identifier of your layer. To find out how to do this, click here

     4. Once your data is ready, click on your Geographic Layer or Data Table > then go to the "Links" tab. The Data tab displays the following information:

           - Maps: This tab shows you the maps that use this data.

          - Data: The first object of the list is the selected layer's data. Other objects are data from linked data tables.

          - Link Data: You can link a layer to multiple data tables if you have modification access to them. You can delete the data join by clicking on the "trash logo".

linked-dataset-list

     5. To link your table with a Geographical Layer, click on "Link Data" > Choose the Unique Identifier column of your Geographical Layer > Choose your Data Table and the Unique Identifier column of your Data Table > Click on "Link Data".

link-data-window

The link column can be different for each link and can contain non-unique values.

The "Links" tab of your geographic layer will now show the Data Table linked to your layer with the Unique Identifier in parenthesis.

link-data-id

Use these joined datasets in a map

In the CartoVista Publisher, you can integrate the joined data to your map, as interactive information, or as a themeset. Go to the Layers properties, in the Data tab.

  1. Click on Add a thematic data table, and enter a name for the attribute table.add-thematic-data-tablethematic-data-table-name
  2. Your new data table will appear in the list view of data. Click on Add thematic data
    add-thematic-data
  3. The window to select data will open, and in the dropdown at the top, you can choose between the original attribute table, and any joined data table :data-table-selection
  4. Select the columns you want to add from this joined data table with the arrows, and click Finish.
  5. The columns will appear in the list view, below the data table entry you have created:layer-properties-two-data-tables

These columns can now be used for interactivity, or in themeset creation:

thematic-anaysis-with-two-data-tables

ℹ️   Once your map is published, the data table name you have chosen will appear on themeset creation, in the column selection of the table view, and as the sheet name of the joined data table when data is exported in Excel.