Counting rows of distinct column in MySQL

Hello folks,

I have a problem in counting the number of rows in a certain distinct column.

I tried like this as the MySQL manual reads,

SELECT COUNT(DISTINCT col_name) from table_name;

but it shows that the statement has a syntax error near 'DISTINCT col_name'

Is there anybody that has a solution for the error?

Thanks in advance,

Jaewoong

$result = mysql_query("SELECT DISTINCT col_name from table_name");

$count = mysql_num_rows($result);

Bring distinct out of the (), SELECT DISTINCT COUNT(col)...

Oops sorry this doesnt work

Hello Louie,

Your answer is definitely right.
I just wanted to make it with one code considering efficiency.

Thank you for answering, Louie!

Jaewoong

Louie wrote:

$result = mysql_query("SELECT DISTINCT col_name from table_name");

$count = mysql_num_rows($result);

Hello kcl,

That's quite alright!
Thank you for your time.

Jaewoong

Oops sorry this doesnt work

I understand your meaning to be that you want to get the number of rows returned, correct? If so, try this:

$result = mysql_query("SELECT DISTINCT col_name from table_name");
#get the number of rows returned from the query
$count = mysql_affected_rows()

Hi, count (distinct ) will not work on 3.22, but i think it does work for 3.23