Syntax error MySQL query to count all the column values from two columns and exclude NULL values in the total count?

MySQL query to count all the column values from two columns and exclude NULL values in the total count?

Let us first create a table −

mysql> create table DemoTable1975
   (
   StudentName varchar(20),
   StudentMarks int
   );
Query OK, 0 rows affected (0.00 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable1975 values('John',45);
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1975 values('Chris',67);
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1975 values('David',59);
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1975 values('Bob',NULL);
Query OK, 1 row affected (0.00 sec)

Display all records from the table using select statement −

mysql> select * from DemoTable1975;

This will produce the following output −

+-------------+--------------+
| StudentName | StudentMarks |
+-------------+--------------+
| John        |           45 |
| Chris       |           67 |
| David       |           59 |
| Bob         |         NULL |
+-------------+--------------+
4 rows in set (0.00 sec)

Here is the query to count all the column values −

mysql> select count(StudentName)+count(StudentMarks) from DemoTable1975;

This will produce the following output −

+----------------------------------------+
| count(StudentName)+count(StudentMarks) |
+----------------------------------------+
|                                      7 |
+----------------------------------------+
1 row in set (0.00 sec)
Updated on: 2019-12-31T07:56:49+05:30

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