Copy Column Value from One table into Another Matching IDs - SQLite

问题

I want to do exactly what it was described in this question: (Copy Column Value from One table into Another Matching IDs), but in SQLite instead of MySQL.

The solution provided:

update t1, t2 set t1.value = t2.p_value where t1.id=t2.parent_id

returns an error near ","... If I say

update t1 set t1.value = t2.p_value where t1.id=t2.parent_id

returns an error near "."

I was not expecting the syntax of MySQL being so different from SQLite.

回答1:

You could try

UPDATE t1 
SET  t1.value = ( 
     SELECT t2.p_value 
     FROM t2 
     WHERE t1.id = t2.parent_id) 

or using you code try

UPDATE t1 
SET value = ( 
  SELECT value 
  FROM t2 
  WHERE t1.id = t2.id)

来源：https://stackoverflow.com/questions/57414183/copy-column-value-from-one-table-into-another-matching-ids-sqlite