LAST_VALUE() - Last Value of Result Set Window

Q

How to obtain the last value of a field expression in the current result set window using the LAST_VALUE() function?

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A

LAST_VALUE(exp) is a MySQL built-in window function that returns the last value of a field expression in the current result set window. For example:

SELECT help_topic_id AS tip, help_category_id AS cid,
  name, LAST_VALUE(name) OVER w
  FROM mysql.help_topic
  WINDOW w AS (PARTITION BY help_category_id);
  -- +-----+-----+----------------+----------------------------+
  -- | tip | cid | name           | LAST_VALUE(name) OVER w    |
  -- +-----+-----+----------------+----------------------------+
  -- |   0 |   1 | HELP_DATE      | HELP_VERSION               |
  -- |   1 |   1 | HELP_VERSION   | HELP_VERSION               |
  -- |   2 |   2 | AUTO_INCREMENT | BLOB DATA TYPE             |
  -- |   6 |   2 | BIT            | BLOB DATA TYPE             |
  -- |   7 |   2 | TINYINT        | BLOB DATA TYPE             |
  -- |   8 |   2 | BOOLEAN        | BLOB DATA TYPE             |
  -- |   9 |   2 | SMALLINT       | BLOB DATA TYPE             |
  -- ...
  -- +-----+-----+----------------+----------------------------+

Reference information of the LAST_VALUE() function:

LAST_VALUE(exp): val
  Returns the last value of a field expression
  in the current result set window.

Arguments, return value and availability:
  exp: Required. The field expression to be evaluated.
  val: Return value. The last value of exp in the current window.
  Available since MySQL 8.

Related MySQL functions:

 

LEAD() - N-Row after Current Row within Window

LAG() - N-Row before Current Row within Window

MySQL Functions on Result Set Windows

⇑⇑ MySQL Function References

2024-09-28, 758🔥, 0💬