Parameter injection not working in BigQuery Vertex AI notebook for WEEK(WEEKDAY)

Question

I'm using a Vertex AI notebook, running BigQuery IPython magics and injecting parameters.

params = {"day_of_week": "WEDNESDAY"}

%%bigquery sales_df --project $project_id --params $params

SELECT created_date, num_sales
FROM sales
WHERE DATE_DIFF(created_date, "2023-01-01", WEEK(@day_of_week)) BETWEEN -12 and 11

I'd expect this to work but it doesn't because WEEK expects a WEEKDAY argument ( BQ docs ). Hardcoding it as WEEK(WEDNESDAY) works but the parameter injection doesn't because it adds quotes around the string, effectively compiling it as WEEK("WEDNESDAY") .

Is there any workaround here? I can't find a BQ method that turns a string weekday ( "WEDNESDAY" ) into the day of week enum ( WEDNESDAY ).

Answer 1

You might try a dynamic SQL in your BigQuery magic.

params = {"day_of_week": "WEDNESDAY"}

%%bigquery sales_df --project $project_id --params $params
EXECUTE IMMEDIATE FORMAT("""
  SELECT created_date, num_sales
  FROM sales
  WHERE DATE_DIFF(created_date, "2023-01-01", WEEK(%s)) BETWEEN -12 and 11
""", @day_of_week);

below is a working example I've tried.

%%bigquery --project your-project-id --params {"day_of_week": "WEDNESDAY"}
EXECUTE IMMEDIATE FORMAT("""
  SELECT DATE_DIFF(CURRENT_DATE, "2023-01-01", WEEK(%s)) BETWEEN -12 and 11
""", @day_of_week)