mysql queries, how to perform these

[Jaunty Edward]

Hello Everyone,

can anyone tell me if I can make a query in mysql of the following type:

select id,msg,topic,COUNT(*) as stats from table GROUP By topic WHERE stats > 20

I only want to select topics that have over 20 msg.

or may be I can do ORDER BY stats DESC to show the topics that have the highest msg.

I think this is a very frequentry requiered thing for webmasters.

Also is there a way in mySQL i can make a query of the following kind.

select * from table where field is empty.

I am sorry I think my msg is not very clearly explaining what I want but I am sure someone out here will surely show me the way.

Thanks

[Mr_Fern]

I believe that the count(*) in your code will count the table. If you're looking to select topics with only 20 messages or more, you may want to set up a field on the topics table which keeps track of the number of messages each topic has. What is this query being used for exactly?

Also is there a way in mySQL i can make a query of the following kind.

select * from table where field is empty.

Use:

SELECT * FROM {tableName} WHERE {fieldName} = ''

[gooflox]

Have you tried the "HAVING" modifier to the "group by"

Something like:

SELECT id, msg, topic, COUNT(*) as stats
FROM table
GROUP By topic
HAVING stats > 20 ;

[Jaunty Edward]

Hi,

Excellent its works... thank you all of you both my problems are solved.

by adding Having I could make a query where topics of that have a specific number are selected.

Thanks once again.
Jaunty