filtering out double entries

[raffael3d]

hi
using a while I just load everything out of the database. Unfortunately there are some double entries in the there in the "topic" column.

what is a function or a way to filter out these double entries?

thanks.

[superwormy]

You could SELECT topic, COUNT(topic) AS topic_count FROM table GROUP BY topic HAVING topic_count > 1 to see which ones are duplicates and delete them...

Alternatively you could SELECT DISTINCT topic FROM table

[raffael3d]

thanks a lot.

deleting is no option. what is happening I am ready data from a Wiki and the "recent changes" lists some topics several times.

however on a different page I only want to list all topics once. so it shows a recent changes site with just recent topics and doesn't list a topic several times.

if I use DISTINCT doesnt it then simply stop when there is a duplicate?

thanks

[superwormy]

If you use distinct it will only select distinct ( different/unique ) records.

[raffael3d]

thanks it works well, however I have the problem now that when using distinct that the topic that has duplicates doesnt show up at all, the goal however should be to display it only once, but not display its duplicates.

what I have so far:
$result = mysql_query("select distinct rc_title from recentchanges WHERE rc_cur_id !='0' order by rc_timestamp desc limit 9")

rc_title is the row where it usually has duplicates.
what can I do?
thanks

[superwormy]

... I think you're mistaken. SELECT DISTINCT should select the first record, but none of the duplicates of that first record it finds.

Make sure the rest of your WHERE clause is not whats excluding the records.