How can I reorder rows in sql database

Question

Is it possible to reorder rows in SQL database? For example; how can I swap the order of 2nd row and 3rd row\'s values?

The order of the row is important to me since

Answer 1

Here is a stored procedure script to increment or decrement (one at a time) in MySQL.

Note, MySQL doesn't allow you to select in the same query you're updating so the above answers don't work.

I have also set it to return an error if there is no item above / below if you're incrementing / decrementing, respectively.

DELIMITER $$
CREATE PROCEDURE `spReorderSequenceItems` (
  IN _SequenceItemId INT,
  IN _SequenceId INT,
  IN IncrementUp TINYINT,
  OUT Error VARCHAR(255)
)

BEGIN
  DECLARE CurrentPosition INT;

  SELECT Position INTO CurrentPosition
  FROM tblSequenceItems
  WHERE SequenceItemId = _SequenceItemId;

  IF IncrementUp = 1 THEN
    IF (
      SELECT Position
      FROM tblSequenceItems 
      WHERE Position = CurrentPosition + 1 AND SequenceId = _SequenceId
    ) THEN
      UPDATE tblSequenceItems
        SET Position = Position - 1
        WHERE Position = CurrentPosition + 1 AND SequenceId = _SequenceId;
      UPDATE tblSequenceItems
        SET Position = Position + 1
        WHERE SequenceItemId = _SequenceItemId;
    ELSE 
      SELECT 'No Item Above' AS _Error INTO Error;
    END IF;
  ELSE
    IF (
      SELECT Position
      FROM tblSequenceItems 
      WHERE Position = CurrentPosition - 1 AND SequenceId = _SequenceId
    ) THEN
      UPDATE tblSequenceItems
        SET Position = Position + 1
        WHERE Position = CurrentPosition - 1 AND SequenceId = _SequenceId;
      UPDATE tblSequenceItems
        SET Position = Position - 1
        WHERE SequenceItemId = _SequenceItemId;
    ELSE
      SELECT 'No Item Below' AS _Error INTO Error;
    END IF;
  END IF;
END
$$
DELIMITER ;

Call it with

CALL spReorderSequenceItems(1, 1, 1, @Error);
SELECT @Error;