Pivot MySQL Table con colonne dinamiche

Immagino il tuo month_payment la colonna è una DATE (a proposito, dovrebbe pubblicare il SHOW CREATE TABLE quando poni domande SQL in modo da non dover indovinare).

Ma la tua prima query non è la formattazione dell'anno/mese. Né limita l'intervallo di date.

SELECT
  GROUP_CONCAT(DISTINCT
    CONCAT(
      'SUM(CASE WHEN EXTRACT(YEAR_MONTH FROM month_payment) = ',
      EXTRACT(YEAR_MONTH FROM month_payment),
      ' THEN AMOUNT END) AS `',
      EXTRACT(YEAR_MONTH FROM month_payment),
      '`'
    )
  ) INTO @sql
FROM record_payment
WHERE month_payment BETWEEN ? AND ?

Vedi https://dev. mysql.com/doc/refman/5.7/en/date-and-time-functions.html#function_extract

Nonostante il suggerimento di Barmar, non c'è motivo di inserirlo in una stored procedure. Hai taggato la tua domanda con PHP e puoi farlo in PHP perfettamente:

<?php

...get a PDO connection...

$sql = "
    SELECT
      GROUP_CONCAT(DISTINCT
        CONCAT(
          'SUM(CASE WHEN EXTRACT(YEAR_MONTH FROM month_payment) = ',
          EXTRACT(YEAR_MONTH FROM month_payment),
          ' THEN AMOUNT END) AS `',
          EXTRACT(YEAR_MONTH FROM month_payment),
          '`'
        )
      ) AS `pivot_columns`
    FROM record_payment
    WHERE month_payment BETWEEN ? AND ?
";
$stmt = $pdo->prepare($sql);
$date_from = '2017-01-01';
$date_to   = '2017-08-01';
$stmt->execute([$date_from, $date_to]);
$row = $stmt->fetch();
$stmt->closeCursor();
$pivot_columns = $row['pivot_columns'];

$sql = "
    SELECT title AS `Payment Method`, {$pivot_columns}
    FROM record_payment t1
    JOIN setting_payment_method spm ON spm.id = t1.method_id
    WHERE month_payment BETWEEN ? AND ?
    GROUP BY title WITH ROLLUP
";
echo $sql;
$stmt = $pdo->prepare($sql);
$stmt->execute([$date_from, $date_to]);
$results = $stmt->fetchAll();
$stmt->closeCursor();

print_r($results);