PostgreSQL - MIN Function
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PostgreSQL MIN function is used to find out the record with minimum value among a record set.
To understand MIN function consider the table COMPANY having records as follows:
testdb# select * from COMPANY; id | name | age | address | salary ----+-------+-----+-----------+-------- 1 | Paul | 32 | California| 20000 2 | Allen | 25 | Texas | 15000 3 | Teddy | 23 | Norway | 20000 4 | Mark | 25 | Rich-Mond | 65000 5 | David | 27 | Texas | 85000 6 | Kim | 22 | South-Hall| 45000 7 | James | 24 | Houston | 10000 (7 rows)
Now suppose based on the above table you want to fetch minimum value of salary, then you can do so simply using the following command:
testdb=# SELECT MIN(salary) FROM company;
Above PostgreSQL statement will produce the following result:
min ------- 10000 (1 row)
You can find all the records with minimum value for each name using GROUP BY clause as follows:
testdb=# SELECT id, name, MIN(salary) FROM company GROUP BY id, name;
Above PostgreSQL statement will produce the following result:
id | name | min ----+-------+------- 4 | Mark | 65000 7 | James | 10000 6 | Kim | 45000 3 | Teddy | 20000 2 | Allen | 15000 5 | David | 85000 1 | Paul | 20000 (7 rows)
You can use MIN Function along with MAX function to find out minimum value as well. Try out following example:
testdb=# SELECT MIN(salary), MAX(salary) max FROM company;
Above PostgreSQL statement will produce the following result:
min | max -------+------- 10000 | 85000 (1 row)
postgresql_useful_functions.htm
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