Get SUM Function in MySQL to Return 0 if No Values are Found

To return Sum as ?0' if no values are found, use IFNULL or COALESCE commands.

The following is the syntax for IFNULL.

SELECT IFNULL(SUM(NULL), 0) AS aliasName;

Let us now implement the above syntax in the following query.

mysql> SELECT IFNULL(SUM(NULL), 0) AS SUMOFTWO;

The following is the output of the above query, which returns 0.

+----------+
| SUMOFTWO |
+----------+
|        0 |
+----------+
1 row in set (0.00 sec)

Here is the syntax for COALESCE.

mysql> SELECT COALESCE(SUM(NULL),0) as SUMOFTWO;

The following is the output that returns 0 using the SUM() function.

+----------+
| SUMOFTWO |
+----------+
|        0 |
+----------+
1 row in set (0.00 sec)