Daevid,

>> > > This is my first trigger I'm trying to write.
>> > > I have two tables. 'stores' and 'zipcodes'.
>> > > I want to automatically set the latitude and longitude of the store using
>> > > it's zipcode lookup in the zipcode table.

>> > > DELIMITER $$;
>> > > DROP TRIGGER `store_coord`$$
>> > > create trigger `store_coord` BEFORE INSERT on `stores`
>> > > for each row BEGIN
>> > >     UPDATE stores AS s, zipcodes AS z
>> > > SET s.latitude = z.latitude,
>> > >     s.longitude = z.longitude
>> > > WHERE s.zip = z.zip AND s.id = NEW.id;
>> > >   END;
>> > > $$

Lose the UPDATE clause. All you need (and all that's permitted) is SET NEW ...
And lose the WHERE clause. It's redundant (also not permitted).
If you need a value from another table, DECLARE a var and write a SELECT INTO for it.
(BTW, if your database looks up latitude & longitude from zipcodes, why bother copying them into store_coord?)

PB


This is my first trigger I'm trying to write.

I have two tables. 'stores' and 'zipcodes'.

I want to automatically set the latitude and longitude of 
      
the store using
    
it's zipcode lookup in the zipcode table.

DELIMITER $$;

DROP TRIGGER `store_coord`$$

create trigger `store_coord` BEFORE INSERT on `stores`
for each row BEGIN
    UPDATE stores AS s, zipcodes AS z
SET s.latitude = z.latitude,
    s.longitude = z.longitude
WHERE s.zip = z.zip AND s.id = NEW.id;
  END;
$$
      
First things first ...

Updating a row that doesn't exist yet (BEFORE INSERT trigger)
doesn't make sense :-)

Why not simply adjust it like this:
new.latitude := <your looked up latitude>
new.longitude := <your looked up longitude>

Given that it's a "before insert", modifying the NEW.<column> values,
these will be stored in the table.
    

  
So when I do this:

insert into `stores` (id, name, zip) values (10,'test 
      
company',  14526);
    
I get this error

Error Code : 1442
Can't update table 'stores' in stored function/trigger because it is
already used by statement which invoked this stored function/trigger.
      

I must not be doing something right, I've tried all these combinations and
ALL give that same error message:

DELIMITER $$;
DROP TRIGGER `store_coord`$$
create trigger `store_coord` BEFORE INSERT on `stores`
	for each row BEGIN
	    UPDATE stores AS s, zipcodes AS z
	SET NEW.latitude = z.latitude,
	    NEW.longitude = z.longitude
	WHERE s.zip = z.zip AND s.id = NEW.id;
  END;
$$

DELIMITER $$;
DROP TRIGGER `store_coord`$$
create trigger `store_coord` BEFORE INSERT on `stores`
	for each row BEGIN
	    UPDATE stores AS s, zipcodes AS z
	SET NEW.latitude := z.latitude,
	    NEW.longitude := z.longitude
	WHERE s.zip = z.zip AND s.id = NEW.id;
  END;
$$

DELIMITER $$;
DROP TRIGGER `store_coord`$$
create trigger `store_coord` AFTER INSERT on `stores`
	for each row BEGIN
	    UPDATE stores AS s, zipcodes AS z
	SET s.latitude = z.latitude,
	    s.longitude = z.longitude
	WHERE s.zip = z.zip AND s.id = NEW.id;
  END;
$$

What am I doing wrong?