MYSQL选择不同的多列

Question

My SQL query looks like this -

SELECT DISTINCT ip, title, url FROM stats

My goal is to select one row for each distinct ip , along with title and url ; however I find when I add the title and url fields to my query it shows me all rows.

Sample Data

ip          title      url
---------------------------
127.0.0.1   title      url
127.0.0.2   title      url
127.0.0.1   difftitle  url

Result I would like

ip          title      url
---------------------------
127.0.0.1   title      url
127.0.0.2   title      url

Answer 1

I think what you are looking for is a query like this -

SELECT 
    ip,
    title,
    url
FROM 
    stats
GROUP BY 
    ip 

GROUP BY is similar to DISTINCT - it means that all results will be grouped by ip , so it will only show one row of results for each distinct ip . However, nothing determines which record will be returned (eg which title and url will be shown).

There is no 'first' entry in the database - a relational database has no 'order' as such, unless you choose to order by a field.