[Standard] Bigquery regex, adding missing dates, and forward filling

query.sql

WITH some_data AS (
  SELECT
    _TDLinx_Store_Code_ as store_code,
    _UPC_ AS upc,
    DATE(PARSE_TIMESTAMP("%m/%d/%Y", (REGEXP_EXTRACT(_Period_Description_Short_, "\\S+\\s*$")))) AS end_date,
    ___ AS dollars,
    _Units_ AS units
  FROM
    `project.dataset.table`
), end_dates AS (
  SELECT
    store_code,
    upc,
    end_date as end_dt
  FROM (
    SELECT
      store_code,
      upc,
      MIN(end_date) min_dt, 
      MAX(end_date) max_dt
    FROM some_data
    GROUP BY
      store_code, upc
  ), UNNEST(GENERATE_DATE_ARRAY(min_dt, max_dt, INTERVAL 1 WEEK)) end_date
)
SELECT 
  LAST_VALUE(dollars IGNORE NULLS) OVER(PARTITION BY end_dates.store_code, end_dates.upc ORDER BY some_data.end_date) dollars,
  LAST_VALUE(units IGNORE NULLS) OVER(PARTITION BY end_dates.store_code, end_dates.upc ORDER BY some_data.end_date) units,
  end_dates.end_dt time_period_end_date,
  end_dates.tdlinx_store_code store_id,
  end_dates.upc upc
FROM
  end_dates
LEFT JOIN
  some_data
ON
  end_dates.store_code = some_data.store_code AND
  end_dates.upc = some_data.upc AND
  end_dates.end_dt = some_data.end_date
ORDER BY
  end_dates.store_code,
  end_dates.upc,
  end_dates.end_dt