MySQL Tutorial/Cursor/Fetch — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
Admin (обсуждение | вклад) м (1 версия) |
(нет различий)
| |
Текущая версия на 09:49, 26 мая 2010
Содержание
Fetch a cursor
mysql>
mysql> CREATE TABLE Employee(
-> id int,
-> first_name VARCHAR(15),
-> last_name VARCHAR(15),
-> start_date DATE,
-> end_date DATE,
-> salary FLOAT(8,2),
-> city VARCHAR(10),
-> description VARCHAR(15)
-> );
Query OK, 0 rows affected (0.01 sec)
mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values (1,"Jason", "Martin", "19960725", "20060725", 1234.56, "Toronto", "Programmer");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(2,"Alison", "Mathews", "19760321", "19860221", 6661.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(3,"James", "Smith", "19781212", "19900315", 6544.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(4,"Celia", "Rice", "19821024", "19990421", 2344.78, "Vancouver","Manager");
Query OK, 1 row affected (0.01 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(5,"Robert", "Black", "19840115", "19980808", 2334.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(6,"Linda", "Green", "19870730", "19960104", 4322.78,"New York", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(7,"David", "Larry", "19901231", "19980212", 7897.78,"New York", "Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(8,"James", "Cat", "19960917", "20020415", 1232.78,"Vancouver", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id | first_name | last_name | start_date | end_date | salary | city | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer |
| 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester |
| 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester |
| 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager |
| 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester |
| 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester |
| 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager |
| 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)
mysql>
mysql>
mysql>
mysql> delimiter $$
mysql>
mysql> CREATE PROCEDURE myProc (in_customer_id INT)
-> BEGIN
->
-> DECLARE l_last_row_fetched int;
-> DECLARE l_id int;
-> DECLARE l_first_name VARCHAR(30);
-> DECLARE l_last_name VARCHAR(30);
->
->
-> DECLARE c1 CURSOR FOR
-> SELECT id,first_name, last_name
-> FROM employee
-> WHERE id=in_customer_id;
->
-> DECLARE CONTINUE HANDLER FOR NOT FOUND SET l_last_row_fetched=1;
->
-> SET l_last_row_fetched=0;
->
->
-> OPEN c1;
-> cursor_loop:LOOP
-> FETCH c1 INTO l_id,l_first_name,l_last_name;
-> IF l_last_row_fetched=1 THEN
-> LEAVE cursor_loop;
-> END IF;
-> /*Do something with the row fetched*/
-> END LOOP cursor_loop;
-> CLOSE c1;
-> SET l_last_row_fetched=0;
->
->
->
-> END$$
Query OK, 0 rows affected (0.02 sec)
mysql> delimiter ;
mysql>
mysql> call myProc(1);
Query OK, 0 rows affected (0.00 sec)
mysql> drop procedure myProc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql>
mysql>
mysql> drop table Employee;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
FETCH Statement
The FETCH statement gets the data from the record, assigns it to a variable, and tells the cursor to move to the next record.
The FETCH statement requires a cursor name and a variable:
FETCH <cursor name> INTO <variable name>[, <variable name>, ... ];
Insert data from a cursor
mysql>
mysql> CREATE TABLE Employee(
-> id int,
-> first_name VARCHAR(15),
-> last_name VARCHAR(15),
-> start_date DATE,
-> end_date DATE,
-> salary FLOAT(8,2),
-> city VARCHAR(10),
-> description VARCHAR(15)
-> );
Query OK, 0 rows affected (0.03 sec)
mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values (1,"Jason", "Martin", "19960725", "20060725", 1234.56, "Toronto", "Programmer");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(2,"Alison", "Mathews", "19760321", "19860221", 6661.78, "Vancouver","Tester");
Query OK, 1 row affected (0.02 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(3,"James", "Smith", "19781212", "19900315", 6544.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(4,"Celia", "Rice", "19821024", "19990421", 2344.78, "Vancouver","Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(5,"Robert", "Black", "19840115", "19980808", 2334.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(6,"Linda", "Green", "19870730", "19960104", 4322.78,"New York", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(7,"David", "Larry", "19901231", "19980212", 7897.78,"New York", "Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(8,"James", "Cat", "19960917", "20020415", 1232.78,"Vancouver", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id | first_name | last_name | start_date | end_date | salary | city | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer |
| 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester |
| 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester |
| 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager |
| 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester |
| 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester |
| 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager |
| 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)
mysql>
mysql>
mysql>
mysql> delimiter $$
mysql>
mysql> CREATE PROCEDURE myProc
-> (p_first_name varchar(30),
-> p_last_name VARCHAR(30),
-> p_city VARCHAR(30),
-> p_description varchar(30),
-> out p_sqlcode int,
-> out p_status_message varchar(100))
-> MODIFIES SQL DATA
-> BEGIN
->
-> DECLARE l_manager_id INT;
-> DECLARE csr_mgr_id cursor for
-> SELECT id
-> FROM employee
-> WHERE first_name=p_first_name AND last_name=p_last_name;
->
-> OPEN csr_mgr_id;
-> FETCH csr_mgr_id INTO l_manager_id;
->
-> INSERT INTO employee (first_name,id,city)
-> VALUES(p_first_name,l_manager_id,p_city);
->
-> CLOSE csr_mgr_id;
-> END$$
Query OK, 0 rows affected (0.00 sec)
mysql> delimiter ;
mysql>
mysql> set @myCode = 0;
Query OK, 0 rows affected (0.00 sec)
mysql> set @myMessage = 0;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> call myProc("Jason","Martin","New City","New Description",@myCode,@myMessage);
Query OK, 1 row affected (0.01 sec)
mysql> drop procedure myProc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id | first_name | last_name | start_date | end_date | salary | city | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer |
| 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester |
| 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester |
| 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager |
| 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester |
| 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester |
| 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager |
| 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |
| 1 | Jason | NULL | NULL | NULL | NULL | New City | NULL |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
9 rows in set (0.00 sec)
mysql>
mysql>
mysql> drop table Employee;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
Leave a cursor fetch
mysql>
mysql>
mysql> CREATE TABLE Employee(
-> id int,
-> first_name VARCHAR(15),
-> last_name VARCHAR(15),
-> start_date DATE,
-> end_date DATE,
-> salary FLOAT(8,2),
-> city VARCHAR(10),
-> description VARCHAR(15)
-> );
Query OK, 0 rows affected (0.03 sec)
mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values (1,"Jason", "Martin", "19960725", "20060725", 1234.56, "Toronto", "Programmer");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(2,"Alison", "Mathews", "19760321", "19860221", 6661.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(3,"James", "Smith", "19781212", "19900315", 6544.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(4,"Celia", "Rice", "19821024", "19990421", 2344.78, "Vancouver","Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(5,"Robert", "Black", "19840115", "19980808", 2334.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(6,"Linda", "Green", "19870730", "19960104", 4322.78,"New York", "Tester");
Query OK, 1 row affected (0.02 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(7,"David", "Larry", "19901231", "19980212", 7897.78,"New York", "Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(8,"James", "Cat", "19960917", "20020415", 1232.78,"Vancouver", "Tester");
Query OK, 1 row affected (0.01 sec)
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id | first_name | last_name | start_date | end_date | salary | city | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer |
| 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester |
| 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester |
| 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager |
| 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester |
| 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester |
| 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager |
| 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)
mysql>
mysql>
mysql>
mysql> delimiter $$
mysql> CREATE PROCEDURE myProc (in_customer_id INT)
-> BEGIN
->
-> DECLARE l_first_name VARCHAR(30);
-> DECLARE l_id INT;
-> DECLARE l_city VARCHAR(30);
-> DECLARE no_more_departments INT;
->
-> DECLARE dept_csr CURSOR FOR
-> SELECT id,first_name, city
-> FROM employee;
->
-> DECLARE CONTINUE HANDLER FOR NOT FOUND SET no_more_departments=1;
->
-> SET no_more_departments=0;
-> OPEN dept_csr;
-> dept_loop:REPEAT
-> FETCH dept_csr INTO l_id,l_first_name,l_city;
-> IF no_more_departments THEN
-> LEAVE dept_loop;
-> END IF;
-> select l_id,l_first_name,l_city;
-> UNTIL no_more_departments
-> END REPEAT dept_loop;
-> CLOSE dept_csr;
-> SET no_more_departments=0;
->
-> END$$
Query OK, 0 rows affected (0.00 sec)
mysql> delimiter ;
mysql> call myProc(1);
+------+--------------+---------+
| l_id | l_first_name | l_city |
+------+--------------+---------+
| 1 | Jason | Toronto |
+------+--------------+---------+
1 row in set (0.02 sec)
+------+--------------+-----------+
| l_id | l_first_name | l_city |
+------+--------------+-----------+
| 2 | Alison | Vancouver |
+------+--------------+-----------+
1 row in set (0.34 sec)
+------+--------------+-----------+
| l_id | l_first_name | l_city |
+------+--------------+-----------+
| 3 | James | Vancouver |
+------+--------------+-----------+
1 row in set (0.34 sec)
+------+--------------+-----------+
| l_id | l_first_name | l_city |
+------+--------------+-----------+
| 4 | Celia | Vancouver |
+------+--------------+-----------+
1 row in set (0.36 sec)
+------+--------------+-----------+
| l_id | l_first_name | l_city |
+------+--------------+-----------+
| 5 | Robert | Vancouver |
+------+--------------+-----------+
1 row in set (0.36 sec)
+------+--------------+----------+
| l_id | l_first_name | l_city |
+------+--------------+----------+
| 6 | Linda | New York |
+------+--------------+----------+
1 row in set (0.36 sec)
+------+--------------+----------+
| l_id | l_first_name | l_city |
+------+--------------+----------+
| 7 | David | New York |
+------+--------------+----------+
1 row in set (0.36 sec)
+------+--------------+-----------+
| l_id | l_first_name | l_city |
+------+--------------+-----------+
| 8 | James | Vancouver |
+------+--------------+-----------+
1 row in set (0.36 sec)
Query OK, 0 rows affected (0.36 sec)
mysql> drop procedure myProc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql>
mysql>
mysql> drop table Employee;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
Output data in a cursor
mysql>
mysql>
mysql> CREATE TABLE Employee(
-> id int,
-> first_name VARCHAR(15),
-> last_name VARCHAR(15),
-> start_date DATE,
-> end_date DATE,
-> salary FLOAT(8,2),
-> city VARCHAR(10),
-> description VARCHAR(15)
-> );
Query OK, 0 rows affected (0.05 sec)
mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values (1,"Jason", "Martin", "19960725", "20060725", 1234.56, "Toronto", "Programmer");
Query OK, 1 row affected (0.02 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(2,"Alison", "Mathews", "19760321", "19860221", 6661.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(3,"James", "Smith", "19781212", "19900315", 6544.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(4,"Celia", "Rice", "19821024", "19990421", 2344.78, "Vancouver","Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(5,"Robert", "Black", "19840115", "19980808", 2334.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(6,"Linda", "Green", "19870730", "19960104", 4322.78,"New York", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(7,"David", "Larry", "19901231", "19980212", 7897.78,"New York", "Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(8,"James", "Cat", "19960917", "20020415", 1232.78,"Vancouver", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id | first_name | last_name | start_date | end_date | salary | city | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer |
| 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester |
| 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester |
| 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager |
| 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester |
| 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester |
| 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager |
| 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)
mysql>
mysql>
mysql>
mysql> delimiter $$
mysql> CREATE PROCEDURE myProc()
-> READS SQL DATA
-> BEGIN
-> DECLARE l_last_row INT DEFAULT 0;
-> DECLARE l_dept_id INT;
-> DECLARE c_dept CURSOR FOR
-> SELECT id
-> FROM employee;
-> /* handler to set l_last_row=1 if a cursor returns no more rows */
-> DECLARE continue handler for NOT FOUND SET l_last_row=1;
->
-> OPEN c_dept;
-> dept_cursor: LOOP
-> FETCH c_dept INTO l_dept_id;
-> IF (l_last_row=1) THEN
-> LEAVE dept_cursor;
-> END IF;
-> select l_dept_id;
->
-> END LOOP dept_cursor;
-> CLOSE c_dept;
->
-> END$$
Query OK, 0 rows affected (0.01 sec)
mysql>
mysql> delimiter ;
mysql> call myProc();
+-----------+
| l_dept_id |
+-----------+
| 1 |
+-----------+
1 row in set (0.00 sec)
+-----------+
| l_dept_id |
+-----------+
| 2 |
+-----------+
1 row in set (0.16 sec)
+-----------+
| l_dept_id |
+-----------+
| 3 |
+-----------+
1 row in set (0.16 sec)
+-----------+
| l_dept_id |
+-----------+
| 4 |
+-----------+
1 row in set (0.16 sec)
+-----------+
| l_dept_id |
+-----------+
| 5 |
+-----------+
1 row in set (0.17 sec)
+-----------+
| l_dept_id |
+-----------+
| 6 |
+-----------+
1 row in set (0.17 sec)
+-----------+
| l_dept_id |
+-----------+
| 7 |
+-----------+
1 row in set (0.17 sec)
+-----------+
| l_dept_id |
+-----------+
| 8 |
+-----------+
1 row in set (0.17 sec)
Query OK, 0 rows affected (0.17 sec)
mysql> drop procedure myProc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql>
mysql>
mysql>
mysql> drop table Employee;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
Using loop and Fetch to read the data in a cursor
mysql>
mysql> CREATE TABLE Employee(
-> id int,
-> first_name VARCHAR(15),
-> last_name VARCHAR(15),
-> start_date DATE,
-> end_date DATE,
-> salary FLOAT(8,2),
-> city VARCHAR(10),
-> description VARCHAR(15)
-> );
Query OK, 0 rows affected (0.01 sec)
mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values (1,"Jason", "Martin", "19960725", "20060725", 1234.56, "Toronto", "Programmer");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(2,"Alison", "Mathews", "19760321", "19860221", 6661.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(3,"James", "Smith", "19781212", "19900315", 6544.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(4,"Celia", "Rice", "19821024", "19990421", 2344.78, "Vancouver","Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(5,"Robert", "Black", "19840115", "19980808", 2334.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(6,"Linda", "Green", "19870730", "19960104", 4322.78,"New York", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(7,"David", "Larry", "19901231", "19980212", 7897.78,"New York", "Manager");
Query OK, 1 row affected (0.01 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(8,"James", "Cat", "19960917", "20020415", 1232.78,"Vancouver", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id | first_name | last_name | start_date | end_date | salary | city | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer |
| 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester |
| 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester |
| 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager |
| 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester |
| 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester |
| 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager |
| 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.02 sec)
mysql>
mysql>
mysql>
mysql> delimiter $$
mysql> CREATE PROCEDURE myProc()
-> BEGIN
-> DECLARE l_sale_id INT;
-> DECLARE l_last_sale INT DEFAULT 0;
->
-> DECLARE sale_csr CURSOR FOR
-> SELECT id
-> FROM employee;
->
-> DECLARE CONTINUE HANDLER FOR NOT FOUND SET l_last_sale=1;
->
-> OPEN sale_csr;
-> sale_loop:LOOP
-> FETCH sale_csr INTO l_sale_id;
-> IF l_last_sale THEN
-> LEAVE sale_loop;
-> END IF;
-> select l_sale_id;
-> END LOOP sale_loop;
-> CLOSE sale_csr;
->
-> END$$
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> delimiter ;
mysql> call myProc();
+-----------+
| l_sale_id |
+-----------+
| 1 |
+-----------+
1 row in set (0.00 sec)
+-----------+
| l_sale_id |
+-----------+
| 2 |
+-----------+
1 row in set (0.13 sec)
+-----------+
| l_sale_id |
+-----------+
| 3 |
+-----------+
1 row in set (0.13 sec)
+-----------+
| l_sale_id |
+-----------+
| 4 |
+-----------+
1 row in set (0.13 sec)
+-----------+
| l_sale_id |
+-----------+
| 5 |
+-----------+
1 row in set (0.13 sec)
+-----------+
| l_sale_id |
+-----------+
| 6 |
+-----------+
1 row in set (0.13 sec)
+-----------+
| l_sale_id |
+-----------+
| 7 |
+-----------+
1 row in set (0.13 sec)
+-----------+
| l_sale_id |
+-----------+
| 8 |
+-----------+
1 row in set (0.13 sec)
Query OK, 0 rows affected (0.13 sec)
mysql> drop procedure myProc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql>
mysql>
mysql> drop table Employee;
Query OK, 0 rows affected (0.00 sec)
mysql>
Using while loop to loop through a cursor
mysql>
mysql> CREATE TABLE Employee(
-> id int,
-> first_name VARCHAR(15),
-> last_name VARCHAR(15),
-> start_date DATE,
-> end_date DATE,
-> salary FLOAT(8,2),
-> city VARCHAR(10),
-> description VARCHAR(15)
-> );
Query OK, 0 rows affected (0.02 sec)
mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values (1,"Jason", "Martin", "19960725", "20060725", 1234.56, "Toronto", "Programmer");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(2,"Alison", "Mathews", "19760321", "19860221", 6661.78, "Vancouver","Tester");
Query OK, 1 row affected (0.02 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(3,"James", "Smith", "19781212", "19900315", 6544.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(4,"Celia", "Rice", "19821024", "19990421", 2344.78, "Vancouver","Manager");
Query OK, 1 row affected (0.02 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(5,"Robert", "Black", "19840115", "19980808", 2334.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(6,"Linda", "Green", "19870730", "19960104", 4322.78,"New York", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(7,"David", "Larry", "19901231", "19980212", 7897.78,"New York", "Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date, salary, City, Description)
-> values(8,"James", "Cat", "19960917", "20020415", 1232.78,"Vancouver", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id | first_name | last_name | start_date | end_date | salary | city | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| 1 | Jason | Martin | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto | Programmer |
| 2 | Alison | Mathews | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester |
| 3 | James | Smith | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester |
| 4 | Celia | Rice | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager |
| 5 | Robert | Black | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester |
| 6 | Linda | Green | 1987-07-30 | 1996-01-04 | 4322.78 | New York | Tester |
| 7 | David | Larry | 1990-12-31 | 1998-02-12 | 7897.78 | New York | Manager |
| 8 | James | Cat | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)
mysql>
mysql>
mysql>
mysql> delimiter $$
mysql> CREATE PROCEDURE myProc (in_customer_id INT)
-> BEGIN
->
-> DECLARE l_first_name VARCHAR(30);
-> DECLARE l_id INT;
-> DECLARE l_city VARCHAR(30);
-> DECLARE l_department_count INT;
-> DECLARE no_more_departments INT;
->
-> DECLARE dept_csr CURSOR FOR
-> SELECT id,first_name, city
-> FROM employee;
->
-> DECLARE CONTINUE HANDLER FOR NOT FOUND SET no_more_departments=1;
->
-> SET no_more_departments=0;
-> OPEN dept_csr;
-> dept_loop:WHILE(no_more_departments=0) DO
-> FETCH dept_csr INTO l_id,l_first_name,l_city;
-> IF no_more_departments=1 THEN
-> LEAVE dept_loop;
-> END IF;
-> SET l_department_count=l_department_count+1;
-> select l_id,l_first_name,l_city;
-> END WHILE dept_loop;
-> CLOSE dept_csr;
-> SET no_more_departments=0;
->
-> END$$
Query OK, 0 rows affected (0.00 sec)
mysql> delimiter ;
mysql>
mysql> call myProc(1);
+------+--------------+---------+
| l_id | l_first_name | l_city |
+------+--------------+---------+
| 1 | Jason | Toronto |
+------+--------------+---------+
1 row in set (0.01 sec)
+------+--------------+-----------+
| l_id | l_first_name | l_city |
+------+--------------+-----------+
| 2 | Alison | Vancouver |
+------+--------------+-----------+
1 row in set (0.01 sec)
+------+--------------+-----------+
| l_id | l_first_name | l_city |
+------+--------------+-----------+
| 3 | James | Vancouver |
+------+--------------+-----------+
1 row in set (0.01 sec)
+------+--------------+-----------+
| l_id | l_first_name | l_city |
+------+--------------+-----------+
| 4 | Celia | Vancouver |
+------+--------------+-----------+
1 row in set (0.01 sec)
+------+--------------+-----------+
| l_id | l_first_name | l_city |
+------+--------------+-----------+
| 5 | Robert | Vancouver |
+------+--------------+-----------+
1 row in set (0.01 sec)
+------+--------------+----------+
| l_id | l_first_name | l_city |
+------+--------------+----------+
| 6 | Linda | New York |
+------+--------------+----------+
1 row in set (0.01 sec)
+------+--------------+----------+
| l_id | l_first_name | l_city |
+------+--------------+----------+
| 7 | David | New York |
+------+--------------+----------+
1 row in set (0.03 sec)
+------+--------------+-----------+
| l_id | l_first_name | l_city |
+------+--------------+-----------+
| 8 | James | Vancouver |
+------+--------------+-----------+
1 row in set (0.03 sec)
Query OK, 0 rows affected (0.03 sec)
mysql>
mysql>
mysql> drop procedure myProc;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>
mysql>
mysql>
mysql>
mysql> drop table Employee;
Query OK, 0 rows affected (0.00 sec)
mysql>