IFNULL函數在MySQL查詢中不起作用

Question

我想要Grand Total的運營商。 但是IFNULL功能不起作用。

SELECT 
      IFNULL(op.operator_name, "Grand Total") AS operator, 
      SUM(re.amount) AS amount 
FROM mobile_db.recharge re 
INNER JOIN mobile_db.operator op 
ON re.operator_id = op.operator_id
GROUP BY operator WITH ROLLUP

Answer 1

您不能將ALIAS用作GROUP BY參數。 請嘗試我的查詢：

SELECT 
     IFNULL(op.operator_name, "Grand Total") AS operator, 
     sum(re.amount) AS amount 
FROM mobile_db.recharge re 
INNER JOIN mobile_db.operator op ON re.operator_id = op.operator_id
GROUP BY IFNULL(op.operator_name, "Grand Total") WITH ROLLUP