Question

宽恕可能无聊的问题。

我正在使用以下示例，即使支出为零，我也想为每个推销员返回一个值。我该如何实现？

SELECT
  CAST(coalesce(customer.salesman, '0') AS integer) as Salesman,
  Sum(sophead.order_value) AS "Quote Value"
FROM
  customer
  INNER JOIN sophead ON sophead.inv_account = customer.account
WHERE
  customer.company = 2 AND
  Extract(MONTH FROM sophead.order_date) = Extract(MONTH FROM Now()) AND
  Extract(YEAR FROM sophead.order_date) = Extract(YEAR FROM Now()) AND
  sophead.order_type = 'Q' AND
  sophead.salesman IN ('21','22','25','28','29','76')
GROUP BY
  customer.salesman
ORDER BY
  customer.salesman

Answer 1

您只需要使用LEFT JOIN和COALESCE来确保无销售时显示为0：

SELECT
  CAST(coalesce(customer.salesman, '0') AS integer) as Salesman,
  COALESCE(Sum(sophead.order_value), 0) AS "Quote Value"
FROM customer
LEFT JOIN sophead 
ON sophead.inv_account = customer.account
AND Extract(MONTH FROM sophead.order_date) = Extract(MONTH FROM Now()) 
AND Extract(YEAR FROM sophead.order_date) = Extract(YEAR FROM Now())
AND sophead.salesman IN ('21','22','25','28','29','76')
WHERE customer.company = 2 
  AND sophead.order_type = 'Q' 
GROUP BY
  customer.salesman
ORDER BY
  customer.salesman

对于左表中的所有行，返回SUM函数的0值

1 个答案: