To JOIN or not to JOIN when updating from another table?

dr_overload

I want to update a field so it's has the same value as a field from another table. Do I need to JOIN the two tables together to achieve this? This is the script I am trying at the moment, which does not include any JOIN.

Example
$result = mysql_query("UPDATE table2 SET field2='table1.field1' WHERE username ='$username'");

Is there anything wrong with this?

Thanks for any assistance

bogu

dr_overload wrote:
Is there anything wrong with this?

Yes, where did u see that approach, where is the reference in the update to table 1?

Why don't u select field1 from table1 and update field2 from table2?

dr_overload

Thank you for replying.

Sorry I'm very new to php mysql script, could I ask - what would be the script to do what you suggest.

Thanks again.

bogu

SELECT field1, username FROM table1

When u colect the results mysql_fetch_assoc() u UPDATE field2 from table2 where username = username from table1 ...