mysql> use test1;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database change
mysql> select * from emp;
+------------+----------+------+--------+
| ename | hiredate | sal | deptno |
+------------+----------+------+--------+
| aaaaa | NULL | NULL | 1 |
| cccccccccc | NULL | NULL | 2 |
| ddddddddd | NULL | NULL | 3 |
| ffffff | NULL | NULL | 4 |
| ggg | NULL | NULL | 5 |
| a1 | NULL | NULL | 5 |
+------------+----------+------+--------+
6 rows in set (0.00 sec)
mysql> show create table emp \G;
*************************** 1. row ***************************
Table: emp
Create Table: CREATE TABLE `emp` (
`ename` varchar(10) DEFAULT NULL,
`hiredate` date DEFAULT NULL,
`sal` decimal(10,2) DEFAULT NULL,
`deptno` int(2) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8
1 row in set (0.01 sec)
ERROR:
No query specified
mysql> DELIMITER &&
mysql> CREATE PROCEDURE num_from_employee (IN input_deptno int, OUT count_num INT )
-> READS SQL DATA
-> BEGIN
-> SELECT COUNT(*) FROM emp WHERE deptno=input_deptno ;
-> END &&
Query OK, 0 rows affected (0.01 sec)
mysql> delimiter ;
mysql> call num_from_employee(5,@a);
+----------+
| COUNT(*) |
+----------+
| 2 |
+----------+
1 row in set (0.02 sec)
Query OK, 0 rows affected (0.02 sec)
mysql> call num_from_employee(1,@a);
+----------+
| COUNT(*) |
+----------+
| 1 |
+----------+
1 row in set (0.01 sec)
Query OK, 0 rows affected (0.01 sec)
mysql> create table inventory(
-> film_id int(11),
-> store_id int(11),
-> inventory_in_stock varchar(50)
-> ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Query OK, 0 rows affected (0.02 sec)
mysql> insert into inventory(film_id,store_id,inventory_in_stock) values (1,2,'aaaaaaaa'), (3,4,'bbbb'), (5,6,'cccccccccc'), (7,8,'dddddd'), (9,10,'fff');
Query OK, 5 rows affected (0.00 sec)
Records: 5 Duplicates: 0 Warnings: 0
mysql> select * from inventory;
+---------+----------+--------------------+
| film_id | store_id | inventory_in_stock |
+---------+----------+--------------------+
| 1 | 2 | aaaaaaaa |
| 3 | 4 | bbbb |
| 5 | 6 | cccccccccc |
| 7 | 8 | dddddd |
| 9 | 10 | fff |
+---------+----------+--------------------+
5 rows in set (0.00 sec)
mysql> delimiter $$
mysql> create procedure film_in_stock(in p_film_id int,in p_store_id int,out p_film_count int)
-> reads sql data
-> begin
-> select film_id
-> from inventory
-> where film_id = p_film_id
-> and store_id = p_store_id;
-> select found_rows() into p_film_count;
-> end $$
Query OK, 0 rows affected (0.01 sec)
mysql> delimiter ;
mysql> call film_in_stock(5,6,@a);
+---------+
| film_id |
+---------+
| 5 |
+---------+
1 row in set (0.01 sec)
Query OK, 1 row affected (0.01 sec)
mysql> show create procedure film_in_stock \G;
*************************** 1. row ***************************
Procedure: film_in_stock
sql_mode:
Create Procedure: CREATE DEFINER=`root`@`localhost` PROCEDURE `film_in_stock`(in p_film_id int,in p_store_id int,out p_film_count int)
READS SQL DATA
begin
select film_id
from inventory
where film_id = p_film_id
and store_id = p_store_id;
select found_rows() into p_film_count;
end
character_set_client: utf8
collation_connection: utf8_general_ci
Database Collation: utf8_general_ci
1 row in set (0.01 sec)
ERROR:
No query specified
mysql> create table actor(
-> actor_id int(11) NOT NULL AUTO_INCREMENT ,
-> first_name varchar(30),
-> last_name varchar(30),
-> PRIMARY KEY (actor_id)
-> ) engine = innodb charset = utf8;
Query OK, 0 rows affected (0.02 sec)
mysql> delimiter $$
mysql> create procedure actor_insert()
-> begin
-> set @x = 1;
-> insert into actor(actor_id,first_name,last_name) values (201,'Test',201);
-> set @x = 2;
-> insert into actor(actor_id,first_name,last_name) values(1,'Test','1');
-> set @x = 3;
-> end $$
Query OK, 0 rows affected (0.01 sec)
mysql> call actor_insert();
Query OK, 0 rows affected (0.02 sec)
mysql> call actor_insert();
ERROR 1062 (23000): Duplicate entry '201' for key 'PRIMARY'
mysql> select @x;
+------+
| @x |
+------+
| 1 |
+------+
1 row in set (0.00 sec)
mysql> delimiter $$
mysql> create procedure actor_insert_new()
-> begin
-> DECLARE CONTINUE HANDLER FOR SQLSTATE '23000' SET @x2 = 1;
-> set @x = 1;
-> insert into actor(actor_id,first_name,last_name) values (201,'Test',201);
-> set @x = 2;
-> insert into actor(actor_id,first_name,last_name) values(1,'Test','1');
-> set @x = 3;
-> end $$
Query OK, 0 rows affected (0.02 sec)
mysql> delimiter ;
mysql> call actor_insert_new();
Query OK, 0 rows affected, 1 warning (0.01 sec)
mysql> call actor_insert_new();
Query OK, 0 rows affected, 1 warning (0.00 sec)
mysql> select @x,@x2;
+------+------+
| @x | @x2 |
+------+------+
| 3 | 1 |
+------+------+
1 row in set (0.00 sec)
mysql> show create table payment \G;
*************************** 1. row ***************************
Table: payment
Create Table: CREATE TABLE `payment` (
`staff_id` int(11) DEFAULT NULL,
`amount` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8
1 row in set (0.01 sec)
ERROR:
No query specified
mysql> select * from payment;
+----------+--------+
| staff_id | amount |
+----------+--------+
| 1 | 10000 |
| 2 | 20000 |
| 3 | 30000 |
| 4 | 400000 |
| 5 | 500000 |
+----------+--------+
5 rows in set (0.01 sec)
mysql> delimiter $$
mysql> create procedure payment_stat()
-> begin
-> DECLARE i_staff_id int;
-> DECLARE d_amount int;
-> declare tmp_name varchar(30) default "";
-> DECLARE cur_payment cursor for select staff_id,amount from payment;
-> DECLARE EXIT HANDLER FOR NOT FOUND CLOSE cur_payment;
->
-> set @x1 = 0 ;
-> set @x2 = 0 ;
->
-> open cur_payment;
-> fetch cur_payment into i_staff_id,d_amount;
-> while(i_staff_id <=3 )
-> do
-> if i_staff_id < 3 then
-> select i_staff_id,d_amount;
-> end if;
-> fetch cur_payment into i_staff_id,d_amount;
-> end while;
-> close cur_payment;
->
-> select @x1,@x2;
-> end;
-> $$
Query OK, 0 rows affected (0.01 sec)
mysql> delimiter ;
mysql> call payment_stat();
+------------+----------+
| i_staff_id | d_amount |
+------------+----------+
| 1 | 10000 |
+------------+----------+
1 row in set (0.01 sec)
+------------+----------+
| i_staff_id | d_amount |
+------------+----------+
| 2 | 20000 |
+------------+----------+
1 row in set (0.01 sec)
+------+------+
| @x1 | @x2 |
+------+------+
| 0 | 0 |
+------+------+
1 row in set (0.01 sec)
Query OK, 0 rows affected (0.01 sec)
mysql> drop procedure payment_stat;
Query OK, 0 rows affected (0.00 sec)
mysql> delimiter $$
mysql> create procedure payment_stat()
-> begin
-> DECLARE i_staff_id int;
-> DECLARE d_amount int;
-> declare tmp_name varchar(30) default "";
-> DECLARE cur_payment cursor for select staff_id,amount from payment;
-> DECLARE EXIT HANDLER FOR NOT FOUND CLOSE cur_payment;
->
-> set @x1 = 0 ;
-> set @x2 = 0 ;
->
-> open cur_payment;
-> fetch cur_payment into i_staff_id,d_amount;
-> while(i_staff_id <=3 )
-> do
-> if i_staff_id < 3 then
-> set @x1 = @x1+ i_staff_id;
-> else
-> set @x2 = @x2+ d_amount;
-> end if;
-> fetch cur_payment into i_staff_id,d_amount;
-> end while;
-> close cur_payment;
->
-> select @x1,@x2;
-> end;
-> $$
Query OK, 0 rows affected (0.01 sec)
mysql> call payment_stat();
-> $$
+------+-------+
| @x1 | @x2 |
+------+-------+
| 3 | 30000 |
+------+-------+
1 row in set (0.01 sec)
Query OK, 0 rows affected (0.01 sec)
mysql> delimiter $$
mysql> create procedure payment_stat()
-> begin
-> DECLARE i_staff_id int;
-> DECLARE d_amount int;
->
-> DECLARE cur_payment cursor for select staff_id,amount from payment;
-> DECLARE EXIT HANDLER FOR NOT FOUND CLOSE cur_payment;
->
-> set @x1 = 0 ;
-> set @x2 = 0 ;
->
-> open cur_payment;
-> fetch cur_payment into i_staff_id,d_amount;
-> while(i_staff_id <=3 )
-> do
-> if i_staff_id < 3 then
-> set @x1 = @x1+ i_staff_id + 1;
-> else
-> set @x2 = @x2+ d_amount ;
-> end if;
-> fetch cur_payment into i_staff_id,d_amount;
-> end while;
-> close cur_payment;
->
-> select @x1,@x2;
-> end;
-> $$
Query OK, 0 rows affected (0.00 sec)
mysql> delimiter ;
mysql> call payment_stat();
+------+-------+
| @x1 | @x2 |
+------+-------+
| 3 | 30000 |
+------+-------+
1 row in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
mysql> drop procedure payment_stat;
Query OK, 0 rows affected (0.00 sec)
mysql> delimiter $$
mysql> create procedure payment_stat()
-> begin
-> DECLARE i_staff_id int;
-> DECLARE d_amount int;
->
-> DECLARE cur_payment cursor for select staff_id,amount from payment;
-> DECLARE EXIT HANDLER FOR NOT FOUND CLOSE cur_payment;
->
-> set @x1 = 0 ;
-> set @x2 = 0 ;
->
-> open cur_payment;
-> fetch cur_payment into i_staff_id,d_amount;
-> while(i_staff_id <=3 )
-> do
-> if i_staff_id < 3 then
-> set @x1 = @x1+ i_staff_id;
-> else
-> set @x2 = @x2+ d_amount;
-> end if;
-> fetch cur_payment into i_staff_id,d_amount;
-> end while;
-> close cur_payment;
->
-> select @x1,@x2;
-> end;
-> $$
Query OK, 0 rows affected (0.00 sec)
mysql> delimiter ;
mysql> call payment_stat();
+------+-------+
| @x1 | @x2 |
+------+-------+
| 3 | 30000 |
+------+-------+
1 row in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
mysql> delimiter $$
mysql> create procedure payment_stat()
-> begin
-> DECLARE i_staff_id int;
-> DECLARE d_amount int;
->
-> DECLARE cur_payment cursor for select staff_id,amount from payment;
-> DECLARE EXIT HANDLER FOR NOT FOUND CLOSE cur_payment;
->
-> set @x1 = 0 ;
-> set @x2 = 0 ;
->
-> open cur_payment;
-> fetch cur_payment into i_staff_id,d_amount;
-> while(i_staff_id <=3 )
-> do
-> if i_staff_id < 3 then
-> set @x1 = @x1+ i_staff_id + 1;
-> else
-> set @x2 = @x2+ d_amount;
-> end if;
-> fetch cur_payment into i_staff_id,d_amount;
-> end while;
-> close cur_payment;
->
-> select @x1,@x2;
-> end;
-> $$
Query OK, 0 rows affected (0.01 sec)
mysql> delimiter ;
mysql> call payment_stat();
+------+-------+
| @x1 | @x2 |
+------+-------+
| 5 | 30000 |
+------+-------+
1 row in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
mysql> drop procedure payment_stat;
Query OK, 0 rows affected (0.02 sec)
mysql> delimiter $$
mysql> create procedure payment_stat()
-> begin
-> DECLARE i_staff_id int;
-> DECLARE d_amount int;
->
-> DECLARE cur_payment cursor for select staff_id,amount from payment;
-> DECLARE EXIT HANDLER FOR NOT FOUND CLOSE cur_payment;
->
-> set @x1 = 0 ;
-> set @x2 = 0 ;
->
-> open cur_payment;
-> fetch cur_payment into i_staff_id,d_amount;
-> while(i_staff_id <=3 )
-> do
-> if i_staff_id < 3 then
-> set @x1 = @x1+ i_staff_id + 6;
-> else
-> set @x2 = @x2+ d_amount + 5;
-> end if;
-> fetch cur_payment into i_staff_id,d_amount;
-> end while;
-> close cur_payment;
->
-> select @x1,@x2;
-> end;
-> $$
Query OK, 0 rows affected (0.01 sec)
mysql> delimiter ;
mysql> call payment_stat();
+------+-------+
| @x1 | @x2 |
+------+-------+
| 15 | 30005 |
+------+-------+
1 row in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
mysql> DELIMITER $$
mysql>
mysql> CREATE PROCEDURE addNum()
-> BEGIN
-> DECLARE x INT;
-> SET x = 0;
-> for_loop : LOOP
-> SET x = x + 1;
-> IF x > 30 THEN
-> LEAVE for_loop;
-> END IF;
-> IF mod(x,2) = 0 then
-> select "num:",x;
-> ITERATE for_loop;
-> END IF;
-> END LOOP;
-> select "count:",x;
-> END $$
Query OK, 0 rows affected (0.01 sec)
mysql> call addNum();
-> $$
+------+------+
| num: | x |
+------+------+
| num: | 2 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 4 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 6 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 8 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 10 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 12 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 14 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 16 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 18 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 20 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 22 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 24 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 26 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 28 |
+------+------+
1 row in set (0.00 sec)
+------+------+
| num: | x |
+------+------+
| num: | 30 |
+------+------+
1 row in set (0.00 sec)
+--------+------+
| count: | x |
+--------+------+
| count: | 31 |
+--------+------+
1 row in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
mysql> delimiter $$
mysql> create procedure repeatPractise()
-> begin
-> set @v = 0 ;
-> REPEAT
-> set @v = @v+ 1;
-> UNTIL @v >=5
-> END REPEAT;
-> END
-> $$
Query OK, 0 rows affected (0.01 sec)
mysql> call repeatPractise();
-> $$
Query OK, 0 rows affected (0.00 sec)
mysql> select @v;
-> $$
+------+
| @v |
+------+
| 5 |
+------+
1 row in set (0.00 sec)
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MySQL vs. Other Programming Languages: A ComparisonApr 19, 2025 am 12:22 AMCompared with other programming languages, MySQL is mainly used to store and manage data, while other languages such as Python, Java, and C are used for logical processing and application development. MySQL is known for its high performance, scalability and cross-platform support, suitable for data management needs, while other languages have advantages in their respective fields such as data analytics, enterprise applications, and system programming.
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SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.
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