Using DISTINCT and COUNT together in a MySQL Query

mysql sql
Click Upvote picture Click Upvote · Jun 16, 2009 · Viewed 202.7k times · Source

Is something like this possible:

SELECT DISTINCT COUNT(productId) WHERE keyword='$keyword'

What I want is to get the number of unique product Ids which are associated with a keyword. The same product may be associated twice with a keyword, or more, but i would like only 1 time to be counted per product ID

Answer

David picture David · Jun 16, 2009

use 

SELECT COUNT(DISTINCT productId) from  table_name WHERE keyword='$keyword'

Related questions

How do I import an SQL file using the command line in MySQL?

I have a .sql file with an export from phpMyAdmin. I want to import it into a different server using the command line. I have a Windows Server 2008 R2 installation. I placed the .sql file on the C drive, and …

Read More
How can I prevent SQL injection in PHP?

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to SQL injection, like in the following example: $unsafe_variable = $_POST['user_input']; mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')"); That's …

Read More
What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN?

What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN in MySQL?

Read More