BigQuery GEOGRAPHY columns not showing in Tableau 2026.2

How can I connect to Spatial data stored in Google BigQuery using Tableau 2026.2? 

According to the Tableau knowledge base I should be able to work with GEOGRAPHY columns when connecting to Google BigQuery directly.  

However I seem to not see the spatial data when connecting.  

I created a test table, to ensure I do not bring in anything but what I want to test. However when dragging in this table the query I can see Tableau uses to fetch the data only select string, float and integers none of the GEOGRAPHY columns.  

When transforming to Custom SQL, and if I hard-code 1 column manually to ensure it is sent, I can see Tableau wraps this into a sub-query. Whilst the outer query is still only selecting non-Geography columns.   

What can I do to connect to spatial data, is there anything I am missing? 

The demo table is build using this query: 

  1 AS id,

  -- 1. BigQuery GEOGRAPHY: POINT

  ST_GEOGPOINT(5.16, 52.77) AS geography_point,

  -- 2. BigQuery GEOGRAPHY: LINESTRING

  ST_GEOGFROMTEXT(

    'LINESTRING(5.10 52.70, 5.20 52.75, 5.30 52.80)'

  ) AS geography_linestring,

  -- 3. BigQuery GEOGRAPHY: POLYGON

  ST_GEOGFROMTEXT(

    'POLYGON((5.0 52.0, 5.1 52.0, 5.1 52.1, 5.0 52.1, 5.0 52.0))'

  ) AS geography_polygon,

-- 4. WKT als STRING: POINT

  'POINT(5.16 52.77)' AS wkt_point,

  -- 5. WKT als STRING: LINESTRING

  'LINESTRING(5.10 52.70, 5.20 52.75, 5.30 52.80)' AS wkt_linestring,

  -- 6. WKT als STRING: POLYGON

  'POLYGON((5.0 52.0, 5.1 52.0, 5.1 52.1, 5.0 52.1, 5.0 52.0))' AS wkt_polygon,

  -- 7. Latitude als FLOAT64

  52.77 AS latitude,

  -- 8. Longitude als FLOAT64

  5.16 AS longitude,

  -- 9. NULL GEOGRAPHY

  CAST(NULL AS GEOGRAPHY) AS geography_null,

  -- 10. GEOGRAPHY via expliciete cast

  CAST(

    ST_GEOGFROMTEXT(

      'POLYGON((5.4 52.0, 5.5 52.0, 5.5 52.1, 5.4 52.1, 5.4 52.0))'

    )

    AS GEOGRAPHY

  ) AS geography_cast

Table in BigQuery  

When converting to Custom query this is the query in Tableau  

When adding geography_point Tableau sends the query as this, with the column in the sub-query but nothing in the outer query