mysql triggers verwijderen

Ik denk dat het kwam door een verwarring met FOR EACH ROW statement.
Het is alleen voor "overeenkomende records voor de instructie die is uitgegeven voordat de trigger wordt aangeroepen. "

Als er N . bestaat aantal records in een tabel en komt overeen met records voor where id=x ,
ervan uitgaande dat x veroorzaakt een resultaat van minder dan N records, zeg N-5 , dan
FOR EACH ROW veroorzaakt een lus voor N-5 keer alleen.

UPDATE :
Een voorbeeld van een testrun op de betreffende rijen vanwege FOR EACH ROW verklaring is hieronder weergegeven.

mysql> -- create a test table
mysql> drop table if exists tbl; create table tbl ( i int, v varchar(10) );
Query OK, 0 rows affected (0.01 sec)

Query OK, 0 rows affected (0.06 sec)

mysql> -- set test data
mysql> insert into tbl values(1,'one'),(2,'two' ),(3,'three'),(10,'ten'),(11,'eleven');
Query OK, 5 rows affected (0.02 sec)
Records: 5  Duplicates: 0  Warnings: 0

mysql> select * from tbl;
+------+--------+
| i    | v      |
+------+--------+
|    1 | one    |
|    2 | two    |
|    3 | three  |
|   10 | ten    |
|   11 | eleven |
+------+--------+
5 rows in set (0.02 sec)

mysql> select count(*) row_count from tbl;
+-----------+
| row_count |
+-----------+
|         5 |
+-----------+
1 row in set (0.00 sec)

mysql>
mysql> -- record loop count of trigger in a table
mysql> drop table if exists rows_affected; create table rows_affected( i int );
Query OK, 0 rows affected (0.02 sec)

Query OK, 0 rows affected (0.05 sec)

mysql> select count(*) 'rows_affected' from rows_affected;
+---------------+
| rows_affected |
+---------------+
|             0 |
+---------------+
1 row in set (0.00 sec)

mysql>
mysql> set @cnt=0;
Query OK, 0 rows affected (0.00 sec)

mysql>
mysql> -- drop trigger if exists trig_bef_del_on_tbl;
mysql> delimiter //
mysql> create trigger trig_bef_del_on_tbl before delete on tbl
    ->   for each row begin
    ->     set @cnt = if(@cnt is null, 1, (@cnt+1));
    ->
    ->     /* for cross checking save loop count */
    ->     insert into rows_affected values ( @cnt );
    ->   end;
    -> //
Query OK, 0 rows affected (0.00 sec)

mysql>
mysql> delimiter ;
mysql>
mysql> -- now let us test the delete operation
mysql> delete from tbl where i like '%1%';
Query OK, 3 rows affected (0.02 sec)

mysql>
mysql> -- now let us see what the loop count was
mysql> select @cnt as 'cnt';
+------+
| cnt  |
+------+
| 3    |
+------+
1 row in set (0.00 sec)

mysql>
mysql> -- now let us see the table data
mysql> select * from tbl;
+------+-------+
| i    | v     |
+------+-------+
|    2 | two   |
|    3 | three |
+------+-------+
2 rows in set (0.00 sec)

mysql> select count(*) row_count from tbl;
+-----------+
| row_count |
+-----------+
|         2 |
+-----------+
1 row in set (0.00 sec)

mysql> select count(*) 'rows_affected' from rows_affected;
+---------------+
| rows_affected |
+---------------+
|             3 |
+---------------+
1 row in set (0.00 sec)

mysql>