MySQL：使用另一个表中的计算更新所有记录

Question

我需要使用2列（mixedPoints和productQuantity）的总和进行计算，其中行属于一个表上的客户（tblSubmissionProducts），然后将该值存储在customer表（tblCustomer）上的客户记录中

1. 需要为每位客户（10k记录）更新。
2. 每个客户在tblSubmissionProducts中可能有0行或更多行。
3. 仅计算mixedPoints值的位置＆gt; 0

我为一位客户创建了一个查询，但它似乎不适用于完整的表

SET @custID = '9';
SELECT customerID, 

(SELECT ROUND(SUM(mixedPointsTotal) / SUM(productQuantity), 2) AS 'Avg Mixed Points' 
FROM tblSubmissionProducts 
WHERE tblSubmissionProducts.customerID = @custID),

(SELECT ROUND(SUM(mixedPointsTotal) / SUM(productQuantity), 2) AS '3mth Mixed Points' 
FROM tblSubmissionProducts 
WHERE tblSubmissionProducts.customerID = @custID
AND submissionProductDate BETWEEN DATE_SUB(NOW(), INTERVAL 3 MONTH) AND NOW()),

(SELECT ROUND(SUM(mixedPointsTotal) / SUM(productQuantity), 2) AS '6mth Mixed Points' 
FROM tblSubmissionProducts 
WHERE tblSubmissionProducts.customerID = @custID
AND submissionProductDate BETWEEN DATE_SUB(NOW(), INTERVAL 6 MONTH) AND NOW())

;

这是该查询的完整列表的第一部分： 它似乎只是锁定表太长时间，只更新一小部分记录。我最终不得不取消查询。

对此有任何帮助将不胜感激。

UPDATE tblCustomer, tblSubmissionProducts
SET  tblCustomer.mixedPoints = 
(SELECT ROUND(SUM(tblSubmissionProducts.mixedPointsTotal) / SUM(tblSubmissionProducts.productQuantity), 2) 
FROM tblSubmissionProducts WHERE tblSubmissionProducts.customerID = tblCustomer.CustomerID
AND tblSubmissionProducts.mixedPoints > 0);

非常感谢提前。

Answer 1

使用MySQL update-join构造，如

UPDATE tblCustomer
JOIN (SELECT customerID,
ROUND(SUM(tblSubmissionProducts.mixedPointsTotal) / SUM(tblSubmissionProducts.productQuantity), 2) as colx
FROM tblSubmissionProducts 
JOIN tblCustomer ON tblSubmissionProducts.customerID = tblCustomer.CustomerID
WHERE tblSubmissionProducts.mixedPoints > 0 ) xxx

ON xxx.customerID = tblCustomer.CustomerID
SET  tblCustomer.mixedPoints = xxx.colx;