How do we use MySQL SUM() function?
#MySQL SUM function is used to calculate the sum of a field in multiple records. To understand the SUM() function, consider an "employee_tbl" table which has 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, assuming based on the above table you want to count the total number of all dialy_typing_pages, then you can use the following command to Complete-
mysql> SELECT SUM(daily_typing_pages) -> FROM employee_tbl; +-------------------------+ | SUM(daily_typing_pages) | +-------------------------+ | 1610 | +-------------------------+ 1 row in set (0.00 sec)
The above is the detailed content of How do we use MySQL SUM() function?. For more information, please follow other related articles on the PHP Chinese website!

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