mysql - 无效操作: column "[column_name]" must appear in the GROUP BY clause or be used in an aggregate function;

Question

我已经阅读了近 10 多个与我的问题相关的问题，但没有人能解决我的问题。因为我的数据库中有 3 个表，我正在尝试计算它们相对于时间的销售额(年销售额)。我需要按date_added对我的查询进行GROUP BY。在 MYSQL 中它工作得很好并且给了我很好的结果，但是在 redshift 中我被卡住了。

MYSQL 查询:

SELECT
MONTHNAME(o.date_added) AS MONTH,
YEAR(o.date_added) AS YEAR,
COUNT(o.order_id) AS orders,
FROM
order o
LEFT JOIN(
SELECT
    op.order_id,
    SUM(op.quantity) AS op_qty,
    SUM(op.total) AS total,
    SUM(op.cost) AS cost
FROM
    order_product op
GROUP BY
    op.order_id
) op
ON
op.order_id = o.order_id
LEFT JOIN(
SELECT
    order_id,
    SUM(IF(CODE = 'coupon', VALUE, 0)) AS coupon
FROM
    order_total
WHERE
    1
GROUP BY
    order_id
) ot
ON
ot.order_id = o.order_id
WHERE
(
    DATE(o.date_added) >= DATE_ADD(NOW(), INTERVAL - 24 MONTH) AND DATE(o.date_added) <= 
DATE(NOW())) AND(o.order_status_id = '22' OR o.order_status_id = '23')
GROUP BY
    MONTH(o.date_added),
    YEAR(o.date_added)
ORDER BY
    date_added ASC
LIMIT 0, 25

这个 MYSQL 查询工作得很好，但是当我将其转换为 RedShift 的 POSTGRE 格式时，它给了我错误 无效操作:列“o.date_added”必须出现在 GROUP BY 子句中或在聚合函数中使用；

POSTGRES 查询:

SELECT
EXTRACT(MONTH FROM o.date_added) AS month,
EXTRACT(YEAR FROM o.date_added) AS year,
COUNT(o.order_id) AS orders
FROM
orders o  
LEFT JOIN
(
    SELECT
        op.order_id,
        SUM(op.quantity) AS op_qty,
        SUM(op.total) AS total,
        SUM(op.cost) AS cost            
    FROM
        order_product op 
    GROUP BY
        op.order_id
) op 
    ON op.order_id = o.order_id             
LEFT JOIN
(
    SELECT
        order_id,
        SUM(CASE 
            WHEN CODE = 'coupon' THEN VALUE 
            ELSE 0 
        END) AS coupon                      
    FROM
        order_total 
    WHERE
        1 
    GROUP BY
        order_id
) ot 
ON ot.order_id = o.order_id                        
WHERE
(
    DATE(o.date_added) >= now() + interval '-24 month' 
    AND DATE(o.date_added) <= DATE(NOW())
)                               
AND (
    o.order_status_id = '22' 
    OR o.order_status_id = '23'
)                               
GROUP BY
(EXTRACT(MONTH FROM o.date_added), EXTRACT(YEAR FROM o.date_added))
ORDER BY
o.date_added ASC LIMIT 25

postgre查询中是否有任何语法错误以及为什么我需要在GROUP BY中添加o.date_add

Answer 1

您的ORDER BY子句中有o.date_added，但您的实际结果集没有它。 ORDER BY 在查询完成后完成。

您可以使用:

ORDER BY month asc, year asc LIMIT 25

此外，您还可以从 GROUP BY 中删除多余的括号:

GROUP BY EXTRACT(MONTH FROM o.date_added), EXTRACT(YEAR FROM o.date_added)

DB-Fiddle

请参阅 Redshift documentation用于使用 now() 函数。使用 getdate() 代替，因为 now() 似乎是 deprecated .