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MySQL SELECT DISTINCT and count?
You need to use GROUP BY command with aggregate function count(*) from MySQL to achieve this. The syntax is as follows:
SELECT yourColumnName,COUNT(*) AS anyVariableNameFROM yourTableName GROUP BY yourColumnName;
To understand the above syntax, let us create a table. The query to create a table is as follows:
mysql> create table selectDistinct_CountDemo -> ( -> Id int NOT NULL AUTO_INCREMENT, -> Name varchar(10), -> AppearanceId int, -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (0.63 sec)
Insert some records in the table using insert command. The query is as follows:
mysql> insert into selectDistinct_CountDemo(Name,AppearanceId) values('Larry',1);
Query OK, 1 row affected (0.18 sec)
mysql> insert into selectDistinct_CountDemo(Name,AppearanceId) values('John',2);
Query OK, 1 row affected (0.24 sec)
mysql> insert into selectDistinct_CountDemo(Name,AppearanceId) values('Larry',3);
Query OK, 1 row affected (0.12 sec)
mysql> insert into selectDistinct_CountDemo(Name,AppearanceId) values('Larry',10);
Query OK, 1 row affected (0.18 sec)
mysql> insert into selectDistinct_CountDemo(Name,AppearanceId) values('Carol',11);
Query OK, 1 row affected (0.18 sec)
mysql> insert into selectDistinct_CountDemo(Name,AppearanceId) values('Larry',15);
Query OK, 1 row affected (0.18 sec)Display all records from the table using select statement. The query is as follows:
mysql> select *from selectDistinct_CountDemo;
The following is the output:
+----+-------+--------------+ | Id | Name | AppearanceId | +----+-------+--------------+ | 1 | Larry | 1 | | 2 | John | 2 | | 3 | Larry | 3 | | 4 | Larry | 10 | | 5 | Carol | 11 | | 6 | Larry | 15 | +----+-------+--------------+ 6 rows in set (0.00 sec)
Here is the query to select distinct and count:
mysql> select Name,count(*) as TotalAppearance from selectDistinct_CountDemo -> group by Name;
The following is the output:
+-------+-----------------+ | Name | TotalAppearance | +-------+-----------------+ | Larry | 4 | | John | 1 | | Carol | 1 | +-------+-----------------+ 3 rows in set (0.00 sec)
Updated on: 30-Jul-2019
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