abt selecting from table

I am sorry but i really guess that u miss the point .
abt ur reply i already know that but thnx anyway.

now here is the scenario :

i got 2 tables :
1- Account_info : with fields : (foreign Key {Prefix_id to prefix into table} , number , subscriber_number )
there is a trigger for this table in order to get the subscriber number using both prefix id and number as in example :
insert into account_info (prefix_id, number ) values (1,9090909) ; ( will automatically insert the subscriber_number with the value that ID 1 refers to and the rest of the number concat (Value(prefix_id(1),number)

2- Prefix_info : with fields: (primary key prefix_id , prefix_value) , this also got a trigger but this trigger works differently .
this trigger is fired when u try to update the prefix value so it looks for all values in account_info table which got the same prefix_id and it will update the subscriber number according to new values.

here is the second trigger code :
Trigger: before_update
Event: UPDATE
Table: prefix_info
Statement: BEGIN
SET @curr_number=0;
SELECT number INTO @curr_number FROM account_info WHERE NEW.prefix_id = account_info.sub_prefix_id;
UPDATE account_info SET account_info.subscriber_id = concat(NEW.prefix_value,@curr_number) WHERE NEW.prefix_id = account_info.sub_prefix_id ;
END

You will notice in this statement "SELECT number INTO @curr_number FROM account_info WHERE NEW.prefix_id = account_info.sub_prefix_id;" that i try to load the number into variable but the query returns more than a single number which cause this error "ERROR 1172 (42000): Result consisted of more than one row" , so i want to enhance that trigger behavior in order to let it update all records not a single one only.

i hope that i make it clear for u know.

and thnx for ur time