SQL/MySQL/Math/Max

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Another MAX function

   <source lang="sql">

/*mysql> select * from employee; +----+-----------+----------+----------------------------+------+---------------+--------+-------+---------------------+ | id | firstname | lastname | title | age | yearofservice| salary | perks | email | +----+-----------+----------+----------------------------+------+---------------+--------+-------+---------------------+ | 1 | John | Chen | Senior Programmer | 31 | 3| 120000 | 25000 | j@hotmail.ru | | 2 | Jan | Pillai | Senior Programmer | 32 | 4| 110000 | 20000 | g@yahoo.ru | | 3 | Ane | Pandit | Web Designer | 24 | 3| 90000 | 15000 | a@gmail.ru | | 4 | Mary | Anchor | Web Designer | 27 | 2| 85000 | 15000 | m@mail.ru | | 5 | Fred | King | Programmer | 32 | 3| 75000 | 15000 | f@net.ru | | 6 | John | Mac | Programmer | 32 | 4| 80000 | 16000 | j@hotmail.ru | | 7 | Arthur | Sam | Programmer | 28 | 2| 75000 | 14000 | e@yahoo.ru | | 8 | Alok | Nanda | Programmer | 32 | 3| 70000 | 10000 | a@yahoo.ru | | 9 | Susan | Ra | Multimedia Programmer | 32 | 4| 90000 | 15000 | h@gmail.ru | | 10 | Paul | Simon | Multimedia Programmer | 23 | 1| 85000 | 12000 | ps@gmail.ru | | 11 | Edward | Parhar | Multimedia Programmer | 30 | 2| 75000 | 15000 | a@hotmail.ru | | 12 | Kim | Hunter | Senior Web Designer | 32 | 4| 110000 | 20000 | kim@coolmail.ru | | 13 | Roger | Lewis | System Administrator | 32 | 3| 100000 | 13000 | roger@mail.ru | | 14 | Danny | Gibson | System Administrator | 31 | 2| 90000 | 12000 | danny@hotmail.ru | | 15 | Mike | Harper | Senior Marketing Executive | 36 | 1| 120000 | 28000 | m@gmail.ru | | 16 | Mary | Sunday | Marketing Executive | 31 | 5| 90000 | 25000 | monica@bigmail.ru | | 17 | Jack | Sim | Marketing Executive | 27 | 1| 70000 | 18000 | hal@gmail.ru | | 18 | Joe | Irvine | Marketing Executive | 27 | 1| 72000 | 18000 | joseph@hotmail.ru | | 19 | Henry | Ali | Customer Service Manager | 32 | 3| 70000 | 9000 | shahida@hotmail.ru | | 20 | Peter | Champion | Finance Manager | 32 | 2| 120000 | 25000 | peter@yahoo.ru | +----+-----------+----------+----------------------------+------+---------------+--------+-------+---------------------+ 20 rows in set (0.00 sec) mysql> select MAX(age) from employee

   ->        where title = "Marketing Executive";

+----------+ | MAX(age) | +----------+ | 31 | +----------+ 1 row in set (0.00 sec)

  • /

Drop table employee; CREATE TABLE employee (

   id int unsigned not null auto_increment primary key,
   firstname varchar(20),
   lastname varchar(20),
   title varchar(30),
   age int,
   yearofservice int,
   salary int,
   perks int,
   email varchar(60)

);

INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("John", "Chen", "Senior Programmer", 31, 3, 120000, 25000, "j@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Jan", "Pillai", "Senior Programmer", 32, 4, 110000, 20000, "g@yahoo.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Ane", "Pandit", "Web Designer", 24, 3, 90000, 15000, "a@gmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Mary", "Anchor", "Web Designer", 27, 2, 85000, 15000, "m@mail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Fred", "King", "Programmer", 32, 3, 75000, 15000, "f@net.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("John", "Mac", "Programmer", 32, 4, 80000, 16000, "j@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Arthur", "Sam", "Programmer", 28, 2, 75000, 14000, "e@yahoo.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Alok", "Nanda", "Programmer", 32, 3, 70000, 10000, "a@yahoo.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Susan", "Ra", "Multimedia Programmer", 32, 4, 90000, 15000, "h@gmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Paul", "Simon", "Multimedia Programmer", 23, 1, 85000, 12000, "ps@gmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Edward", "Parhar", "Multimedia Programmer", 30, 2, 75000, 15000, "a@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Kim", "Hunter", "Senior Web Designer", 32, 4, 110000, 20000, "kim@coolmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Roger", "Lewis", "System Administrator", 32, 3, 100000, 13000, "roger@mail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Danny", "Gibson", "System Administrator", 31, 2, 90000, 12000, "danny@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Mike", "Harper", "Senior Marketing Executive", 36, 1, 120000, 28000, "m@gmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Mary", "Sunday", "Marketing Executive", 31, 5, 90000, 25000, "monica@bigmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Jack", "Sim", "Marketing Executive", 27, 1, 70000, 18000, "hal@gmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Joe", "Irvine", "Marketing Executive", 27, 1, 72000, 18000, "joseph@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Henry", "Ali", "Customer Service Manager", 32, 3, 70000, 9000, "shahida@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Peter", "Champion", "Finance Manager", 32, 2, 120000, 25000, "peter@yahoo.ru");

select * from employee; select MAX(age) from employee

      where title = "Marketing Executive";
 
          
      </source>
   
  


Simple MAX

   <source lang="sql">

/*mysql> select * from employee; +----+-----------+----------+----------------------------+------+---------------+--------+-------+---------------------+ | id | firstname | lastname | title | age | yearofservice| salary | perks | email | +----+-----------+----------+----------------------------+------+---------------+--------+-------+---------------------+ | 1 | John | Chen | Senior Programmer | 31 | 3| 120000 | 25000 | j@hotmail.ru | | 2 | Jan | Pillai | Senior Programmer | 32 | 4| 110000 | 20000 | g@yahoo.ru | | 3 | Ane | Pandit | Web Designer | 24 | 3| 90000 | 15000 | a@gmail.ru | | 4 | Mary | Anchor | Web Designer | 27 | 2| 85000 | 15000 | m@mail.ru | | 5 | Fred | King | Programmer | 32 | 3| 75000 | 15000 | f@net.ru | | 6 | John | Mac | Programmer | 32 | 4| 80000 | 16000 | j@hotmail.ru | | 7 | Arthur | Sam | Programmer | 28 | 2| 75000 | 14000 | e@yahoo.ru | | 8 | Alok | Nanda | Programmer | 32 | 3| 70000 | 10000 | a@yahoo.ru | | 9 | Susan | Ra | Multimedia Programmer | 32 | 4| 90000 | 15000 | h@gmail.ru | | 10 | Paul | Simon | Multimedia Programmer | 23 | 1| 85000 | 12000 | ps@gmail.ru | | 11 | Edward | Parhar | Multimedia Programmer | 30 | 2| 75000 | 15000 | a@hotmail.ru | | 12 | Kim | Hunter | Senior Web Designer | 32 | 4| 110000 | 20000 | kim@coolmail.ru | | 13 | Roger | Lewis | System Administrator | 32 | 3| 100000 | 13000 | roger@mail.ru | | 14 | Danny | Gibson | System Administrator | 31 | 2| 90000 | 12000 | danny@hotmail.ru | | 15 | Mike | Harper | Senior Marketing Executive | 36 | 1| 120000 | 28000 | m@gmail.ru | | 16 | Mary | Sunday | Marketing Executive | 31 | 5| 90000 | 25000 | monica@bigmail.ru | | 17 | Jack | Sim | Marketing Executive | 27 | 1| 70000 | 18000 | hal@gmail.ru | | 18 | Joe | Irvine | Marketing Executive | 27 | 1| 72000 | 18000 | joseph@hotmail.ru | | 19 | Henry | Ali | Customer Service Manager | 32 | 3| 70000 | 9000 | shahida@hotmail.ru | | 20 | Peter | Champion | Finance Manager | 32 | 2| 120000 | 25000 | peter@yahoo.ru | +----+-----------+----------+----------------------------+------+---------------+--------+-------+---------------------+ 20 rows in set (0.00 sec) mysql> select MAX(salary) from employee

   ->        where title = "Programmer";

+-------------+ | MAX(salary) | +-------------+ | 80000 | +-------------+ 1 row in set (0.00 sec)

  • /

Drop table employee; CREATE TABLE employee (

   id int unsigned not null auto_increment primary key,
   firstname varchar(20),
   lastname varchar(20),
   title varchar(30),
   age int,
   yearofservice int,
   salary int,
   perks int,
   email varchar(60)

);

INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("John", "Chen", "Senior Programmer", 31, 3, 120000, 25000, "j@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Jan", "Pillai", "Senior Programmer", 32, 4, 110000, 20000, "g@yahoo.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Ane", "Pandit", "Web Designer", 24, 3, 90000, 15000, "a@gmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Mary", "Anchor", "Web Designer", 27, 2, 85000, 15000, "m@mail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Fred", "King", "Programmer", 32, 3, 75000, 15000, "f@net.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("John", "Mac", "Programmer", 32, 4, 80000, 16000, "j@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Arthur", "Sam", "Programmer", 28, 2, 75000, 14000, "e@yahoo.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Alok", "Nanda", "Programmer", 32, 3, 70000, 10000, "a@yahoo.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Susan", "Ra", "Multimedia Programmer", 32, 4, 90000, 15000, "h@gmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Paul", "Simon", "Multimedia Programmer", 23, 1, 85000, 12000, "ps@gmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Edward", "Parhar", "Multimedia Programmer", 30, 2, 75000, 15000, "a@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Kim", "Hunter", "Senior Web Designer", 32, 4, 110000, 20000, "kim@coolmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Roger", "Lewis", "System Administrator", 32, 3, 100000, 13000, "roger@mail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Danny", "Gibson", "System Administrator", 31, 2, 90000, 12000, "danny@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Mike", "Harper", "Senior Marketing Executive", 36, 1, 120000, 28000, "m@gmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Mary", "Sunday", "Marketing Executive", 31, 5, 90000, 25000, "monica@bigmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Jack", "Sim", "Marketing Executive", 27, 1, 70000, 18000, "hal@gmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Joe", "Irvine", "Marketing Executive", 27, 1, 72000, 18000, "joseph@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Henry", "Ali", "Customer Service Manager", 32, 3, 70000, 9000, "shahida@hotmail.ru"); INSERT INTO employee (firstname, lastName, title, age, yearofservice, salary, perks, email) values ("Peter", "Champion", "Finance Manager", 32, 2, 120000, 25000, "peter@yahoo.ru"); select * from employee;

select MAX(salary) from employee

      where title = "Programmer";


      </source>
   
  


Use MAX to get the largest value

   <source lang="sql">

/* mysql> SELECT * FROM report; +---------+--------+-------+ | article | dealer | price | +---------+--------+-------+ | 0001 | A | 4.45 | | 0001 | B | 5.45 | | 0002 | A | 16.67 | | 0003 | B | 6.12 | | 0003 | C | 2.78 | | 0003 | D | 2.34 | | 0004 | D | 21.29 | +---------+--------+-------+ 7 rows in set (0.01 sec) mysql> /* The Row Holding the Maximum of a Certain Column */ mysql> SELECT article, dealer, price

   -> FROM   report
   -> WHERE  price=(SELECT MAX(price) FROM report);

+---------+--------+-------+ | article | dealer | price | +---------+--------+-------+ | 0004 | D | 21.29 | +---------+--------+-------+ 1 row in set (0.00 sec)

  • /

Drop table report;

CREATE TABLE report (

      article INT(4) UNSIGNED ZEROFILL DEFAULT "0000" NOT NULL,
      dealer  CHAR(20)                 DEFAULT ""     NOT NULL,
      price   DOUBLE(16,2)             DEFAULT "0.00" NOT NULL,
      PRIMARY KEY(article, dealer));

INSERT INTO report VALUES (1,"A",4.45),

                       (1,"B",5.45),
                       (2,"A",16.67),
                       (3,"B",6.12),
                       (3,"C",2.78),
                       (3,"D",2.34),
                       (4,"D",21.29);
   

SELECT * FROM report;

/* The Row Holding the Maximum of a Certain Column */ SELECT article, dealer, price FROM report WHERE price=(SELECT MAX(price) FROM report);

      </source>