Question

I have two tables, structured like so:

table A:
   A_ID    varchar(32) PRIMARY KEY
   field1  varchar(255)
   field2  varchar(255)
   B_ID    varchar(32)

table B:
   B_ID    varchar(32) PRIMARY KEY
   field1  varchar(255)
   field2  varchar(255)

A contains a foreign key to table B (note that 1 B could have more than 1 A). I’d like to insert the data from table B to it’s matching table A (field1 and field2 is empty for every row in table A currently). Is there a way to do this purely with MySQL?

Answer 1

Try

UPDATE `table_a` AS a 
INNER JOIN `table_b` AS b ON ( a.`b_id` = b.`id` ) 
SET a.`field1` = b.`field1`, a.`field2` = b.`field2`