Count zero, NULL and distinct values except zero and NULL with a single MySQL query

MySQLMySQLi Database

Let us first create a table −

mysql> create table DemoTable(
   Value int
);
Query OK, 0 rows affected (1.35 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable values(10);
Query OK, 1 row affected (0.30 sec)
mysql> insert into DemoTable values(NULL);
Query OK, 1 row affected (0.29 sec)
mysql> insert into DemoTable values(10);
Query OK, 1 row affected (0.59 sec)
mysql> insert into DemoTable values(0);
Query OK, 1 row affected (0.23 sec)
mysql> insert into DemoTable values(20);
Query OK, 1 row affected (0.27 sec)
mysql> insert into DemoTable values(10);
Query OK, 1 row affected (0.70 sec)
mysql> insert into DemoTable values(0);
Query OK, 1 row affected (0.15 sec)
mysql> insert into DemoTable values(NULL);
Query OK, 1 row affected (0.16 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable;

This will produce the following output −

+-------+
| Value |
+-------+
| 10    |
| NULL  |
| 10    |
| 0     |
| 20    |
| 10    |
| 0     |
| NULL  |
+-------+
8 rows in set (0.00 sec)

Following is the query to group by on all values except null and 0 −

mysql> select sum(Value is null) as NumberOfNull,
   sum(Value=0) as NumberOfZero,
   count(distinct Value > 0) as ValueExceptZeroAndNull
from DemoTable;

This will produce the following output −

+--------------+--------------+------------------------+
| NumberOfNull | NumberOfZero | ValueExceptZeroAndNull |
+--------------+--------------+------------------------+
| 2            | 2            | 2                      |
+--------------+--------------+------------------------+
1 row in set (0.00 sec)
raja
Published on 27-Sep-2019 07:40:35
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