对于使用MySQL 5.7的prestashop用户

UPDATE
    ps_stock_available sa
    INNER JOIN ps_shop s
        ON sa.id_shop = s.id_shop AND s.id_shop = 1
    INNER JOIN ps_order_detail od
        ON sa.id_product = od.product_id AND od.id_order = 22417
SET
    sa.physical_quantity = sa.quantity + sa.reserved_quantity

这是一个例子，但重点正如埃里克在这里所说https://stackoverflow.com/a/1293347/5864034

您需要在FIRST处添加UPDATE语句，其中包含要连接的所有表的完整地址，然后添加SET语句

后期的，后期的

UPDATE table1
SET    COLUMN = value
FROM   table2,
       table3
WHERE  table1.column_id = table2.id
       AND table1.column_id = table3.id
       AND table1.COLUMN = value
       AND table2.COLUMN = value
       AND table3.COLUMN = value 

SQL不是真正可移植的另一个例子。

对于MySQL，应该是：

update ud, sale
set ud.assid = sale.assid
where sale.udid = ud.id;

有关更多信息，请阅读多表更新：http://dev.mysql.com/doc/refman/5.0/en/update.html

UPDATE [LOW_PRIORITY] [IGNORE] table_references
    SET col_name1={expr1|DEFAULT} [, col_name2={expr2|DEFAULT}] ...
    [WHERE where_condition]

PostgreSQL：

CREATE TABLE ud (id integer, assid integer);
CREATE TABLE sales (id integer, udid integer, assid integer);

UPDATE ud
SET assid = sales.assid
FROM sales
WHERE sales.id = ud.id;

试试这个吧，我想这对你有用

update ud

set ud.assid = sale.assid

from ud 

Inner join sale on ud.id = sale.udid

where sale.udid is not null

标准的SQL方法是

UPDATE ud
SET assid = (SELECT assid FROM sale s WHERE ud.id=s.id)

在SQL Server上，可以使用联接

UPDATE ud
SET assid = s.assid
FROM ud u
JOIN sale s ON u.id=s.id