Update ...From（Cross Join in Update）：sqlite 不支持类似的update，替代的解决办法是:
UPDATE table1 SET col2 = (select col2 from table2 where table2.col1=table1.col1 limit 1)
where exists(select * from table2 where table2.col1=table1.col1);
原文链接：https://www.f2er.com/sqlite/199458.html