MySQL MAX Function

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MySQL MAX function is used to find out the record with maximum value among a record set.

To understand MAX function, consider an employee_tbl table, which is having the following records:

mysql> SELECT * FROM employee_tbl;
+------+------+------------+--------------------+
| id   | name | work_date  | daily_typing_pages |
+------+------+------------+--------------------+
|    1 | John | 2007-01-24 |                250 |
|    2 | Ram  | 2007-05-27 |                220 |
|    3 | Jack | 2007-05-06 |                170 |
|    3 | Jack | 2007-04-06 |                100 |
|    4 | Jill | 2007-04-06 |                220 |
|    5 | Zara | 2007-06-06 |                300 |
|    5 | Zara | 2007-02-06 |                350 |
+------+------+------------+--------------------+
7 rows in set (0.00 sec)

Now, suppose based on the above table you want to fetch maximum value of daily_typing_pages, then you can do so simply using the following command:

mysql> SELECT MAX(daily_typing_pages)
    -> FROM employee_tbl;
+-------------------------+
| MAX(daily_typing_pages) |
+-------------------------+
|                     350 |
+-------------------------+
1 row in set (0.00 sec)

You can find all the records with maximum value for each name using GROUP BY clause as follows:

mysql> SELECT id, name, MAX(daily_typing_pages)
    -> FROM employee_tbl GROUP BY name;
+------+------+-------------------------+
| id   | name | MAX(daily_typing_pages) |
+------+------+-------------------------+
|    3 | Jack |                     170 |
|    4 | Jill |                     220 |
|    1 | John |                     250 |
|    2 | Ram  |                     220 |
|    5 | Zara |                     350 |
+------+------+-------------------------+
5 rows in set (0.00 sec)

You can use MIN Function along with MAX function to find out minimum value as well. Try out the following example:

mysql> SELECT MIN(daily_typing_pages) least, MAX(daily_typing_pages) max
    -> FROM employee_tbl;
+-------+------+
| least | max  |
+-------+------+
|   100 |  350 |
+-------+------+
1 row in set (0.01 sec)


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