Question

I am trying to update a row called ctcode in a table called partnumber copying values from the row ctcode in a table called families. My SQL statement however returns and “Unknown Column ‘families.parent’ in ‘where clause'” error.

Here is my SQL Statement

UPDATE `partnumber` 
SET `partnumber`.`ctcode`=`families`.`ctcode` 
WHERE `partnumber`.`partnumber`=`families`.`parent`;

What is wrong with my statement? Is there any more efficient way of doing this?

Answer 1

You can basically join both tables even in UPDATE statements,

UPDATE `partnumber` a INNER JOIN `families` b
          ON a.`partnumber` = b.`parent`
SET    a.`ctcode`= b.`ctcode`