这在SQL Server中应该有效：

update ud 
set assid = sale.assid
from sale
where sale.udid = id

Teradata Aster提供了实现目标的另一种有趣方式：

MERGE INTO ud --what table should be updated
USING sale -- from what table/relation update info should be taken
ON ud.id = sale.udid --join condition
WHEN MATCHED THEN 
    UPDATE SET ud.assid = sale.assid; -- how to update

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;

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 

这在SQL Server中应该有效：

update ud 
set assid = sale.assid
from sale
where sale.udid = id

在MS ACCESS中：

UPDATE ud 
INNER JOIN sale ON ud.id = sale.udid
SET ud.assid = sale.assid;