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-- tables must have time attribute, e.g. `bidtime` in this table
> desc Bid;
+-------------+------------------------+------+-----+--------+---------------------------------+
|        name |                   type | null | key | extras |                       watermark |
+-------------+------------------------+------+-----+--------+---------------------------------+
|     bidtime | TIMESTAMP(3) *ROWTIME* | true |     |        | `bidtime` - INTERVAL '1' SECOND |
|       price |         DECIMAL(10, 2) | true |     |        |                                 |
|        item |                 STRING | true |     |        |                                 |
+-------------+------------------------+------+-----+--------+---------------------------------+

-- Flink 1.19
> SELECT window_start, window_end, item, SUM(price) AS total_price
  FROM TABLE(
      SESSION(TABLE Bid PARTITION BY item, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES))
  GROUP BY item, window_start, window_end;
  
-- VVR 8.x
> SELECT window_start, window_end, item, SUM(price) AS total_price
  FROM TABLE(
      SESSION(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES))
  GROUP BY item, window_start, window_end;

-- 包含對window_start的過濾
> SELECT window_start, window_end, item, SUM(price) AS total_price
    FROM
    (SELECT item, price, window_start, window_end FROM
    TABLE(
    SESSION(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES))
    where window_start >= TIMESTAMP '2020-04-15 08:06:00.000')
    GROUP BY item, window_start, window_end;
  
-- 包含對window_start的計算
> SELECT window_start, window_end, item, SUM(price) AS total_price
    FROM
    (SELECT item, price, window_start + (INTERVAL '1' SECOND) as window_start, window_end FROM
    TABLE(
    SESSION(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES)))
    GROUP BY item, window_start, window_end;

-- 包含對window_start的計算
> SELECT window_start, window_end, item, SUM(price) AS total_price
    FROM
    (SELECT item, price, CAST(window_start as varchar) as window_start, window_end FROM
    TABLE(
    SESSION(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES)))
    GROUP BY item, window_start, window_end;

> SELECT window_start, window_end, category, SUM(price) AS total_price
    FROM
    (SELECT category, price, window_start, window_end FROM
    TABLE(
    SESSION(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES)),
    LATERAL TABLE(category_udtf(item)) as T(category))
    GROUP BY category, window_start, window_end;

 SELECT window_start, item, SUM(price) AS total_price
  FROM TABLE(
      SESSION(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES))
  GROUP BY item, window_start;

> SELECT item, SUM(price) AS total_price
  FROM TABLE(
      SESSION(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES))
  GROUP BY GROUPING SETS((item), (window_start), (window_end));
  
> SELECT item, SUM(price) AS total_price
  FROM TABLE(
      SESSION(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES))
  GROUP BY CUBE (item, window_start, window_end);
  
> SELECT item, SUM(price) AS total_price
  FROM TABLE(
      SESSION(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES))
  GROUP BY ROLLUP (item, window_start, window_end);

> SELECT window_start, window_end, item, SUM(price) AS total_price, max(window_end) AS max_end
  FROM TABLE(
      SESSION(TABLE Bid, DESCRIPTOR(bidtime), INTERVAL '5' MINUTES))
  GROUP BY item, window_start, window_end;