Date Calculations: extract parts of dates : Date Function « Date Time « SQL / MySQL





Date Calculations: extract parts of dates

 
/*

mysql> select * from Bird;
+----------+-------+---------+------+------------+-------+
| name     | owner | species | sex  | birth      | death |
+----------+-------+---------+------+------------+-------+
| BlueBird | Joe   | Car     | f    | 1999-03-30 | NULL  |
| RedBird  | Yin   | Bus     | m    | 1979-04-30 | NULL  |
| RedBird  | Yin   | Bus     | m    | 1998-01-30 | NULL  |
+----------+-------+---------+------+------------+-------+
3 rows in set (0.00 sec)

mysql> /*how old each a Bird is*/
mysql> SELECT name, birth, CURDATE(),
    ->        (YEAR(CURDATE())-YEAR(birth))
    ->         - (RIGHT(CURDATE(),5)<RIGHT(birth,5))
    ->        AS age
    ->        FROM Bird;
+----------+------------+------------+------+
| name     | birth      | CURDATE()  | age  |
+----------+------------+------------+------+
| BlueBird | 1999-03-30 | 2005-10-11 |    6 |
| RedBird  | 1979-04-30 | 2005-10-11 |   26 |
| RedBird  | 1998-01-30 | 2005-10-11 |    7 |
+----------+------------+------------+------+
3 rows in set (0.00 sec)


*/  
Drop table Bird;

CREATE TABLE Bird (
    name VARCHAR(20), 
    owner VARCHAR(20),
    species VARCHAR(20), 
    sex CHAR(1), 
    birth DATE, 
    death DATE
);
  
INSERT INTO  Bird VALUES ('BlueBird','Joe','Car','f','1999-03-30',NULL);
INSERT INTO  Bird VALUES ('RedBird','Yin','Bus','m','1979-04-30',NULL);
INSERT INTO  Bird VALUES ('RedBird','Yin','Bus','m','1998-01-30',NULL);
  
select * from Bird;
  

/*how old each a Bird is*/


SELECT name, birth, CURDATE(),
       (YEAR(CURDATE())-YEAR(birth))
        - (RIGHT(CURDATE(),5)<RIGHT(birth,5))
       AS age
       FROM Bird;
           
         
  










Related examples in the same category

1.Date data type manipulation
2.Get Day of Month for a date
3.Get the YEAR part of the date
4.Birthdays in the upcoming month
5.DATE_ADD() add a time interval to a given date
6.Calculation on Date data type
7.Date Calculations: calculate ages
8.Get sub date
9.Decomposing Dates or Times Using String Functions substrings.
10.Pull out the entire date or time part from DATETIME values using string-extraction functions such as LEFT( ) o