複数のSQL文を記述する場合は、BEGIN〜ENDでくくる

mysql> CREATE PROCEDURE sp_2()
    -> BEGIN
    -> INSERT INTO t_tokui VALUES(1010,'得意先11');
    -> UPDATE t_tokui SET tkname = '得意先名10' WHERE tkcd = 1010;
    -> END
    -> //
Query OK, 0 rows affected (0.02 sec)

mysql> CALL sp_2()//
Query OK, 1 row affected (0.06 sec)

mysql> delimiter ;
mysql> select * from t_tokui;
+------+------------+
| tkcd | tkname     |
+------+------------+
| 1001 | 得意先名1  |
| 1002 | 得意先名2  |
| 1003 | 得意先名3  |
| 1004 | 得意先名4  |
| 1005 | 得意先名5  |
| 1010 | 得意先名10 |
+------+------------+
6 rows in set (0.00 sec)