Question

我有一个错误说＆＃34;您的SQL语法有错误;查看与您的MySQL服务器版本相对应的手册，以便在＃table; FROM table_A INNER JOIN table_B ON table_A.name = table_B.name＆＃39;附近使用正确的语法。在第1行＆＃34;

sql查询是：

$sql="UPDATE table_A SET table_A.quantity = table_A.quantity -  
table_B.quantity FROM table_A INNER JOIN table_B ON table_A.name = table_B.name 
WHERE table_B.status = 'APPROVED'";

请帮我解决这个错误。谢谢。

Answer 1

＆＃34; INNER＆＃34;应该是＆＃34; INNER JOIN＆＃34;

我认为你还必须拿出＆＃34; table_A＆＃34;来自＆＃34; SET quantity＆＃34;

 $sql="UPDATE table_A SET quantity = table_A.quantity -  
    table_B.quantity FROM table_A INNER JOIN table_B ON table_A.name = table_B.name 
    WHERE table_B.status = 'APPROVED'";

Answer 2

您有语法错误。

使用UPDATE更正INNER JOIN的语法：

UPDATE T1,T2
[INNER JOIN | LEFT JOIN] T1 ON T1.C1 = T2. C1
SET T1.C2 = T2.C2, 
    T2.C3 = expr
WHERE condition

查询：

$sql="UPDATE table_A 
INNER JOIN table_B ON table_A.name = table_B.name 
SET table_A.quantity = table_A.quantity - table_B.quantity
WHERE table_B.status = 'APPROVED'";

SQL语法错误：＆＃39; FROM table_A INNER JOIN table_B ON table_A.name = table_B.name＆＃39;第1行

2 个答案: