update script help

need help creating update script.

[Lighthater]

I'm having a really hard time making a script to update fields in mysql. I managed to make the add script, but haven't been able to figure out a simple update script. Can someone help out? I just need to do a form where the user can input updated data in to keep it current. Here is what the database looks like:

 mysql> explain users;
+-------------------+-----------------------+------+-----+------------+-----------------+
¦ Field    ¦ Type     ¦ Null ¦ Key ¦ Default ¦ Extra ¦
+-------------------+-----------------------+------+-----+------------+-----------------+
¦ user_id   ¦ mediumint(8) unsigned ¦  ¦ PRI ¦ NULL  ¦ auto_increm ent ¦
¦ username   ¦ varchar(20)   ¦ YES ¦  ¦ NULL  ¦ ¦
¦ first_name  ¦ varchar(15)   ¦  ¦  ¦   ¦  ¦
¦ last_name   ¦ varchar(30)   ¦  ¦  ¦   ¦  ¦
¦ email    ¦ varchar(40)   ¦ YES ¦  ¦ NULL  ¦  ¦
¦ password   ¦ varchar(16)   ¦  ¦  ¦   ¦  ¦
¦ registration_date ¦ date     ¦  ¦  ¦ 0000-00-00 ¦  ¦
¦ link    ¦ varchar(60)   ¦  ¦  ¦   ¦  ¦
¦ da    ¦ varchar(25)   ¦  ¦  ¦ unknown ¦  ¦
+-------------------+-----------------------+------+-----+------------+-----------------+
9 rows in set (0.00 sec)
 
mysql>

[bobnew32]

update [phpfreaks.com] table_name set field= 'info' where id= '1'

Sample sql query above. Very simple.