PHP，mysqli的，如何從列綁定參數和使用他們的

Question

我想選擇不同的用戶NUM1與NUM2：

$stmt = $mysqli->prepare('SELECT `num1`, `num2` FROM `Mytable1` WHERE `user` in (SELECT DISTINCT `user` from `Mytable1` where type=2)'); 
$stmt->execute(); 
$stmt->bind_result($num1, $num2); 
$stmt->store_result(); 
$stmt->fetch(); 
$stmt->close(); 

我需要得到的結果$result = $num1 * $num2;

在隨後輸入結果Mytable2

$stmt = $mysqli->prepare('UPDATE `Mytable2` SET `num`=? WHERE `name` in (SELECT DISTINCT `user` FROM bookmaker_bets WHERE type=2)'); 
$stmt->bind_param('i', $result); 
$stmt->execute(); 
$stmt->close(); 

如何使num1和num2從每個用戶中選擇，而不是第一個用戶？

Answer 1

您可以執行此更新一個SQL語句：

UPDATE table2 
    INNER JOIN users ON users.userId = table2.userId 
    INNER JOIN table1 ON table1.userId = users.userId 
SET table2.result = table1.num1 * table1.num2 
WHERE users.type = 2; 

請參閱this fiddle