MySQL Tutorial/Procedure Function/Select Into

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Save select result into a variable

   <source lang="sql">

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 (0.02 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 (0.01 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()

   ->   READS SQL DATA
   -> BEGIN
   ->   DECLARE winner_id INT;
   ->   DECLARE max_employee_id INT;
   ->   DECLARE winner_name VARCHAR(70);
   ->
   ->   SELECT MAX(id)
   ->     INTO max_employee_id
   ->     FROM employee;
   ->
   ->   SET winner_id=FLOOR(RAND()*max_employee_id)+1;
   ->
   ->   SELECT CONCAT_WS(" ","Employee of the week is",first_name,last_name)
   ->     FROM employee
   ->    WHERE id=winner_id;
   -> END$$

Query OK, 0 rows affected (0.00 sec) mysql> mysql> delimiter ; mysql> call myProc(); +---------------------------------------------------------------+ | CONCAT_WS(" ","Employee of the week is",first_name,last_name) | +---------------------------------------------------------------+ | Employee of the week is James Smith | +---------------------------------------------------------------+ 1 row in set (0.00 sec) 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> mysql> mysql> drop table Employee; Query OK, 0 rows affected (0.02 sec)</source>


Select into variables

   <source lang="sql">

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 (0.00 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_first_name  VARCHAR(30);
   ->      DECLARE l_last_name   VARCHAR(30);
   ->      DECLARE l_city        VARCHAR(30);
   ->
   ->      SELECT first_name, last_name,city
   ->        INTO l_first_name,l_last_name,l_city
   ->        FROM employee
   ->       WHERE id=in_customer_id;
   ->
   ->      select l_first_name;
   ->      select l_last_name;
   ->      select l_city;
   ->
   -> END$$

Query OK, 0 rows affected (0.00 sec) mysql> mysql> delimiter ; mysql> call myProc(1); +--------------+ | l_first_name | +--------------+ | Jason | +--------------+ 1 row in set (0.00 sec) +-------------+ | l_last_name | +-------------+ | Martin | +-------------+ 1 row in set (0.00 sec) +---------+ | l_city | +---------+ | Toronto | +---------+ 1 row in set (0.00 sec) Query OK, 0 rows affected (0.00 sec) mysql> 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></source>


Using SELECT ... INTO is a method for setting variables.

SELECT ... INTO allows you to query a table and push the results into a variable as a part of the query.

SELECT ... INTO works only if you are selecting a single row of data:



   <source lang="sql">

mysql> mysql> 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 (0.01 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> mysql> mysql> mysql> drop table Employee; Query OK, 0 rows affected (0.00 sec) mysql> mysql> Set @myInt = 0; Query OK, 0 rows affected (0.00 sec) mysql> SELECT COUNT(*) INTO @myInt FROM employee; ERROR 1146 (42S02): Table "test.employee" doesn"t exist mysql> select @myInt; +--------+ | @myInt | +--------+ | 0 | +--------+ 1 row in set (0.00 sec) mysql> mysql> --You can also select multiple values into multiple variables: SELECT id,name INTO new_id,new_name FROM employee LIMIT 1; mysql> mysql> mysql></source>