标准sql语句
update AA set AA.name = BB.name , AA.sex = BB.sex from BB where AA.id = BB.id ;
注意不要写成 from AA,BB ，即不要把自身的表写在from后，不然会报异常 ：table name specified more than once
update AA set name = BB.name from AA,BB where AA.id = BB.id
标准sql语句,可以同时更新多个列
UPDATE BB set (name,sex) = (select CC.name, CC.sex from CC where CC.id = BB.id) where BB.id = 1
update A SET A.COL1=B.COL1 FROM A,B where A.KEY=B.KEY where 其它条件限制
原文：https://www.cnblogs.com/whatlonelytear/p/11649747.html